hybridfree/eevblog-posts huggingface dataset:
Marchand balun layout - Page 1
Forum section: electronics / rf-microwave

author: promach
author_rank: Frequent Contributor
timestamp: May 30, 2019, 03:02:39 am
content: Forthis marchand balun schematics in ADS, how toinstructthe ADS layout generator to use coil shape (for area saving in IC) ?Besides, anyone have any experience withplanar layout of marchand balun on PCB?balun schematicsgenerated balun layout not in coil shapebalun layout in coil shape

author: pigrew
author_rank: Frequent Contributor
timestamp: May 30, 2019, 03:19:19 am
content: I have minimal experience with ADS, but my feeling is that you'll need to go the opposite way: Draw the layout and simulate it using Momentum (or HFSS?), and import that s-parameter block into ADS.ADS seems to have somedocumentation on that simulation flow.

author: promach
author_rank: Frequent Contributor
timestamp: May 31, 2019, 07:16:31 am
content: Someone else told me to replaceCLINwith2 Symmetrical Coupled Microstrip Lines (MCP)and then use linecalc to get the correct length and width.What do you think about this idea ?

author: tec5c
author_rank: Frequent Contributor
timestamp: June 12, 2019, 03:21:40 pm
content: You're asking to transform a cell (MCP) which is two straight lines into a spiral. This is not practical. So you need to look at alternatives.You can use pre-existing spiral cells available in default ADS library. Such as; MSIND, MRIND, MSSPLS_MDS, MSSPLC_MDS and so on. All of these have layouts associated to them.You can use a PDK which has spiral inductors and layouts. (Least probable option, mainly aimed at design houses).You can manually design the spiral inductor layout yourself, then run EM sim. to optimise the design to your liking and use the layout as a cell in your circuit design.Or you can manually design the entire balun within the layout window and run EM sims on the whole design (most common option).

author: promach
author_rank: Frequent Contributor
timestamp: June 16, 2019, 10:50:16 am
content: QuoteYes, I am now trying to replicateplanar layout of marchand balun on PCBusing SonnetLite instead.This bookMicrostrip Filters for RF Microwave Applicationshas some good examples (maths theory + implementation) on microstrip filters, but not balun.

author: promach
author_rank: Frequent Contributor
timestamp: June 19, 2019, 06:20:14 am
content: How do we see from the following expressions thateven-mode to odd-mode impedance ratio is very important for balun?How to derive the expressions involving Ya， Yb， Zoe，Zoo ?And why need to increase Zoe/Zoo impedance ratio ?

author: promach
author_rank: Frequent Contributor
timestamp: September 08, 2019, 04:46:11 am
content: Seehttps://github.com/promach/planar_marchand_balunI suppose I made mistake in the width of the coupled microstrip (W=2mm) in terms of ports impedance of 50 ohm ??
Experiments on 13cm - 2.4 GHz over mountains (non line of sight) - Page 1
Forum section: electronics / rf-microwave

author: haydenph
author_rank: Contributor
timestamp: August 24, 2019, 09:23:55 am
content: An on air contact with my 2.4 gigahertz transverter and FT817. The path is not line of sight and is over 1200m (4000 feet) mountains. Amazing signal considering the path and the location of my grid pack.

author: Lord of nothing
author_rank: Super Contributor
timestamp: September 10, 2019, 04:04:07 pm
content: Output Power?

author: PA0PBZ
author_rank: Super Contributor
timestamp: September 10, 2019, 05:55:39 pm
content: Quote from: Lord of nothing on September 10, 2019, 04:04:07 pmDid you watch the video?

author: Lord of nothing
author_rank: Super Contributor
timestamp: September 10, 2019, 06:37:37 pm
content: No dont run on my Virtual Pc.

author: Yansi
author_rank: Super Contributor
timestamp: September 10, 2019, 06:44:58 pm
content: We did around ~650km contact on a 9cm (3400MHz) band last summer. Also not line of sight. SNR was pisspoor, but enough for CW. Our station using a 75cm dish and a 15W PA.Not sure WTF or how the f did it happen, but it was working.
The Icom IC-705! HF-UHF SDR Radio - An initial review - Page 1
Forum section: electronics / rf-microwave

author: haydenph
author_rank: Contributor
timestamp: September 07, 2019, 11:41:51 am
content: A truly exciting announcement from Icom at the Toyko Hamfair 2019!! The new Icom IC-705 was a topic of discussion and review at a recent experimenters night at our local ham radio club.Rex VK7MO, Justin VK7TW and Hayden VK7HH gave their thoughts on what this new Icom IC-705 radio can mean for the QRP, microwave or SOTA operators. Some features like a large touchscreen just like the IC-7300 or IC-9700 will appeal to users who already own one or both of these radios.

author: awallin
author_rank: Frequent Contributor
timestamp: September 07, 2019, 04:55:25 pm
content: I wish these ham rigs would have full I/Q input and output, via USB or Ethernet, just like the USRP SDRs, and compatibility with common SDR-software (e.g. gnu-radio).how hard can that be...

author: djacobow
author_rank: Super Contributor
timestamp: September 08, 2019, 04:28:51 pm
content: I suspect these manufacturers see it as a turf thing. Giving I/Q output (and heck, why not I/Q input for tx, too) means their rigs become front ends and half the radio (and associated value) ends up in your computer.Long term, they can't win this battle.Related thing in HTs, where no major will put in DMR even though they could do do for, umm, nothing.

author: borjam
author_rank: Unknown
timestamp: September 08, 2019, 07:32:54 pm
content: At least the Icom IC-7300 can be configured to send I+Q via USB. The bandwidth will be small, though.

author: Lord of nothing
author_rank: Super Contributor
timestamp: September 10, 2019, 04:02:30 pm
content: Well for most European who life in an Apartment the should make a "Black Box" without any Physical Input and with an USB and Ethernet Port to put them under the Roof and use it via the Ethernet only.
ICOM PCR-1000 / uPC1037GR SSB product detector chip, EU source? - Page 1
Forum section: electronics / rf-microwave

author: 9aplus
author_rank: Regular Contributor
timestamp: September 05, 2019, 11:25:08 am
content: Looking for uPC1037GR replacement chip present in some ICOM and Kenwood RX and TRXAny EU source is much appreciatedHave nice old ICOM PCR1000 with problem on SSB & CWthe rest is working UFBPSE / TNX for any assistance

author: CJay
author_rank: Super Contributor
timestamp: September 05, 2019, 05:26:23 pm
content: Will Icom not supply it?

author: 9aplus
author_rank: Regular Contributor
timestamp: September 05, 2019, 06:07:51 pm
content: That is possible,but so far managed only to find some option from ICOM America....Do you have link for ICOM EU parts source, please?

author: CJay
author_rank: Super Contributor
timestamp: September 05, 2019, 09:07:22 pm
content: https://icomuk.co.uk/Icom-Spares

author: 9aplus
author_rank: Regular Contributor
timestamp: September 10, 2019, 08:13:21 am
content: Just to note...Before ordering I decided to measure all known points again.... on my surprise find out that uPC1037 may be in order,the next one is CD4066 chip switching all audio. All is switched UFB except SSB. Than what?! Logic... possible?Before next step decided to try with other control SW, initially used the last version of original ICOM PCR SW on Win10.Next choice Talk PCR v3 beta.On first run after serial port adjusted, SSB and CW are working!For some reason original ICOM PCR SW faulty recognized PCR-100 instead of PCR-1000,for me that is only logical explanation.Thank you all for reading... hope to save someone else from painNext step, attempt to run Raspberry PI image, with PCR AnyWhere 2.2.1 in server mode...
Derivation of Marchand Balun equations - Page 1
Forum section: electronics / rf-microwave

author: promach
author_rank: Frequent Contributor
timestamp: September 06, 2019, 05:51:28 pm
content: Could anyone advise aboutderivation of Marchand Balun Equations?Note: Screenshot below is taken from paper :New Design Formulas for Impedance-Transforming 3-dB Marchand Baluns

author: promach
author_rank: Frequent Contributor
timestamp: September 10, 2019, 09:17:42 am
content: Analysis and design of impedance-transforming planar Marchand balunstalks about the derivation process, but it is still not complete.We still need to derive equation (1) of the paper.Update:Microwave Engineering by David Pozarhas some details on deriving the coupling coefficient equation.Equation (7.84) is derived accordingly as below :Update 2:David Pozar's book only deals with symmetric coupled lines, but do not deal with unsymmetric coupled linesSee figure 9 ofCoupled Transmission Line Networks in an Inhomogeneous Dielectric MediumAs you notice, Marchand Balun design uses the middle and the right topology below :
Deriving admittance matrix for shortened quarter-wavelength transmission line - Page 1
Forum section: electronics / rf-microwave

author: promach
author_rank: Frequent Contributor
timestamp: August 30, 2019, 09:51:54 am
content: ForReduced-size branch-line and rat-race hybrids for uniplanar MMIC's, how to derive equation (2) ?and is the imaginary constantjneeded in equation (1) ?

author: T3sl4co1l
author_rank: Super Contributor
timestamp: August 30, 2019, 12:26:04 pm
content: 1. Yup. Unless the line is lossy, in which case you need some real component as well.2. Start from the definition of a transmission line (AC steady state), and of the admittance matrix.Tim

author: promach
author_rank: Frequent Contributor
timestamp: September 01, 2019, 01:48:11 am
content: For equation (1) , I am trying to useMATLAB y2abcd() functionto convert admittance matrix to ABCD matrix.However, I am getting mismatch between MATLAB answer and actual theoretical result.

author: promach
author_rank: Frequent Contributor
timestamp: September 06, 2019, 08:03:17 am
content: For equation (2) , is thismultiplicationcorrect?Once I use, I am getting correct values for A and D, but not for C.I have extra negative sign for C.Could anyone advise why ?
Fisher TFM1000 pulse count detector-How does it work? - Page 1
Forum section: electronics / rf-microwave

author: djsb
author_rank: Super Contributor
timestamp: September 07, 2019, 11:21:26 am
content: I'm trying to understand how the switch,pulse counter and averaging filter stage of the Fisher TFM1000 tuner works. I have read a copy of an article by A H Seidman from Electronics World Jan 1967 (link below). Attached is an LTspice file I have created in an effort to try to understand how the circuit works.The first 3 limiter stages are straightforward. It is the switch, delay line, pulse counter and averaging filter that I don't understand (centre around Q5,Q6 and L3 in the LTSpice schematic and Q905/906 and L902 in the original schematic). I have cross-referenced the article above with the service manual and L3 is just marked 500 (it does not indicate nH,uH, or mH). However, the photo of the unit shows a coil mounted on a ferrite rod. This could be the delay line. Could someone help me to figure this out? I'm just curious as to how this novel detector works and in particular how would a 25nS delay line be implemented as well. Thanks.PS The text file attached is the LTSpice file. Please change the text file extension to .asc. The pdf file is a page from the service manual with the limiter/detector schematic. The article mentioned above is too large to upload. Here is a link to ithttps://www.americanradiohistory.com/Archive-Electronics-World/60s/1967/Electronics-World-1967-01.pdf

author: vk6zgo
author_rank: Super Contributor
timestamp: September 08, 2019, 01:29:27 am
content: For a basic idea on how pulse counting FM detectors work, watch this:-
FM front end with varicap tuning - Page 1
Forum section: electronics / rf-microwave

author: aurelZ
author_rank: Contributor
timestamp: September 24, 2019, 10:06:41 am
content: HiAnyone know where i can found schematic - design for two bipolar transistorsFM frontend with varicap diode tuning.thnx

author: CJay
author_rank: Super Contributor
timestamp: September 24, 2019, 10:12:20 am
content: little bit more info?Frequencies of interest and application for a start but there are numerous PMR radios which use varicap tuned front ends

author: aurelZ
author_rank: Contributor
timestamp: September 26, 2019, 07:07:34 am
content: more info..okschematic for FM front end for 88-108 Mhz superhet receiverwith bipolar transistors

author: ogden
author_rank: Super Contributor
timestamp: September 26, 2019, 07:15:13 am
content: http://circuit-zone.com/index.php?cat=fm_radio_receivers

author: aurelZ
author_rank: Contributor
timestamp: September 26, 2019, 06:09:44 pm
content: ThanksBut on well known given link there is no any FM front end for superhet radio receiver.is there somehing concrete,,,?

author: PA0PBZ
author_rank: Super Contributor
timestamp: September 26, 2019, 06:20:11 pm
content: From here:http://earmark.net/gesr/sr3.htmJust google FM frontendhttps://www.google.com/search?q=fm+front+end+schematic&safe=strict&source=lnms&tbm=isch

author: aurelZ
author_rank: Contributor
timestamp: September 27, 2019, 06:47:58 am
content: WOWthank you PAOPBZ this one looking very hi-fiok i will trythnx..
Mike's Radio Repair is Back! - Page 1
Forum section: electronics / rf-microwave

author: German_EE
author_rank: Super Contributor
timestamp: December 02, 2018, 11:44:58 am
content: In case you were missing our favorite CB repair guy, he's back! I haven't added everything up properly but there's about eight hours of videos to work through, just the thing for a wet Sunday afternoon.https://www.youtube.com/user/trclubricants/videos

author: GreyWoolfe
author_rank: Unknown
timestamp: December 02, 2018, 01:11:56 pm
content: That's awesome. I concerned that the hurricane trashed his domicile. Time to catch up.

author: Radio Tech
author_rank: Frequent Contributor
timestamp: December 04, 2018, 03:22:12 pm
content: I know Mike pretty well. He is good at what he does.Problem is that he is so busy. Whenever he post videos he is flooded with mail.Which takes him from his back log.Was great to see him post more videos. He has hundreds of videos that have not been posted.

author: pa4mic
author_rank: Newbie
timestamp: September 01, 2019, 09:34:16 pm
content: Is hè again stopped?

author: German_EE
author_rank: Super Contributor
timestamp: September 04, 2019, 05:20:52 pm
content: Looks like it, he must have a hell of a backlog!
RF de-coupling with ferrite bead vs. RF choke, can it degrade S/N ratio? - Page 1
Forum section: electronics / rf-microwave

author: szoftveres
author_rank: Regular Contributor
timestamp: August 30, 2019, 06:10:07 pm
content: Hello All,I'm building a front-end section for a VHF receiver; the traditional method for de-coupling (e.g. varicap tuning voltage, transistor gate / base bias voltage) or loading these circuits is by using a sufficiently large RF choke, or resistors in some instances.Resistors are not perfect at the 100MHz band, as they have stray capacitance, hence many times RF chokes are necessary.However I found it really hard to find a sufficiently large inductance, that also has a high enough self-resonant frequency (SRF) that would fit my application.So I figured out that I could maybe still use resistors, butslide a small ferrite bead on the resistor leadat thehotend; the ferrite bead acts like a true resistance (no reactive component) at high frequencies, and would be able to cancel out all the stray capacitance of the resistor, to whose lead it had been slid on, thereby providing the necessary impedance.I have a lot of these beads so I tried them on an oscillator + buffer; looks like working fine.My question is that could this method of de-coupling have any adverse effect on the performance of a front-end of a receiver?Since ferrite beads act like true resistive elements at high frequencies, my suspicion is that they introduce some thermal noise (Johnson-Nyquist noise). Any shared knowledge or experience on this topic would be much appreciated.

author: David Hess
author_rank: Super Contributor
timestamp: August 31, 2019, 03:41:54 am
content: Ferrite beads for EMI applications are designed to be lossy so the added impedance at high frequencies is low. They do make special ferrite beads for wideband input bias current applications however.Parasitic capacitance of the resistors can be lowered by using several in series so the resistances add and the parasitic capacitances divide.The capacitance of the transistor limits input impedance to lower values anyway so extra high impedance at the input is not required. If you use an input transformer, then DC bias can be provided through it at low impedance.

author: pigrew
author_rank: Frequent Contributor
timestamp: August 31, 2019, 04:02:58 am
content: Quote from: szoftveres on August 30, 2019, 06:10:07 pmHave you looked atCoilCraft's bias inductors? I've used them in the past at higher frequencies, but I assume they would work well for you (as they have high (more than a kiloohm) impedance around 100 Mhz). They have a 165 uF model (SRF ~ 60 MHz) and 3.5uF (SRF ~ 188 MHz) among others.However, you've gotten me thinking about if the ferrite would degrade the NF... We could simulate it?
Deriving microstrip stub equations - Page 1
Forum section: electronics / rf-microwave

author: promach
author_rank: Frequent Contributor
timestamp: September 25, 2019, 12:23:25 am
content: Do anyone know how to derive themicrostrip stub equationsfor all four microstrip below ?

author: IconicPCB
author_rank: Super Contributor
timestamp: September 25, 2019, 12:39:05 am
content: Use a Smith chart
Help me identify this dongle? - Page 1
Forum section: electronics / rf-microwave

author: pbarton
author_rank: Frequent Contributor
timestamp: August 29, 2019, 05:50:10 pm
content: Bought a scope recently and this device was in the lid.Can you identify what it is, preferably with a manufacturers name/model number?I suspect that its missing a probe (with a TNC connector) of some description.The only marking is 'SMA 13'

author: pbarton
author_rank: Frequent Contributor
timestamp: August 29, 2019, 08:19:57 pm
content: Initially thought it may be a 'standard probe compensation network'.However, a 'standard probe compensation network' is designed to give the probe a flat response across a wide range of frequencies.This device contains a tuned circuit, which is unlikely to give a flat response.Looks quite old, could date back to 1960's or 1970's?

author: pbarton
author_rank: Frequent Contributor
timestamp: August 30, 2019, 09:25:16 am
content: Connected it between an oscillator and a scope.It appears to be a low pass device. No attenuation at frequencies below 1MHz.3dB point around 3MHz.So, maybe it is a ‘probe compensation network’?

author: magic
author_rank: Super Contributor
timestamp: August 30, 2019, 10:42:45 am
content: I think you would have more luck moving this thread to the RF subforum.There should be a button for that at the bottom of this page.

author: StillTrying
author_rank: Super Contributor
timestamp: August 30, 2019, 11:30:29 am
content: It looks like a TNC connector version of these.https://www.thorlabs.com/newgrouppage9.cfm?objectgroup_id=8613

author: pbarton
author_rank: Frequent Contributor
timestamp: August 30, 2019, 02:46:14 pm
content: As THORlabs are selling low pass filters, as a front end input for a scope, then I have to assume that there is indeed a market for a low pass probe.I don’t think that I have ever encountered one before.Probes with BNC connectors are the norm nowadays, although I have some old Tektronix P6006 probes using the PL-259 connector.I don’t think that I have ever encountered a probe using a TNC connector before. Has anybody out there seen a probe using a TNC connector?

author: szoftveres
author_rank: Regular Contributor
timestamp: August 30, 2019, 09:49:58 pm
content: Reminds me of the dongles that allowed cable viewers to watch HBO on analog TV sets in the '90s.HBO came through the cable network along with all other channels, but it came modulated with a 2-3MHz signal, so that it was unwatchable for the general public.HBO subscribers got a small dongle that they had to install in series of the antenna cable, that filtered out this particular signal. It was a very simple filter circuit, so it was often replicated by "pirate" HBO watchers.Couldn't find a picture of a legit one, but here's how the pirate versions looked like::https://translate.google.com/translate?sl=hu&tl=en&u=http%3A%2F%2Fwww.szetszedtem.hu%2F193hbo%2Fdekoderek.htm
SIM7000 MQTT re-connection issue. - Page 1
Forum section: electronics / rf-microwave

author: utpal19
author_rank: Newbie
timestamp: August 30, 2019, 09:30:53 am
content: Hello,According toSIM7000_Series_MQTT_Application_notesfrom here:https://www.waveshare.com/w/upload/d/d0/SIM7000_Series_MQTT_Application_Note_V1.00.pdfThere are MQTT commands which makes it easier to handle and maintain MQTT connection. While I connect to MQTT broker by usingAT+SMCONNcommand (which connect and maintain the connection) it works fine and connect to MQTT broker but if I restart my device when it's already connected to MQTT broker and try to reconnect again usingAT+SMCONNcommand it takes too longer(aprx 4-5 mins) to connect again. Any help to fix this issue is welcome.Thank you.**I am Sorry for my English guys.
Free (RF) Energy ?? - Page 1
Forum section: electronics / rf-microwave

author: German_EE
author_rank: Super Contributor
timestamp: August 24, 2019, 04:15:37 pm
content: No, I don't believe in this free energy stuff either, which is why I need your help solving a puzzle.I have a 10 MHz GPSDO that is connected to a distribution amplifier built from op amps, output impedance is about 5 ohms per channel and I see a 5.25V P-P signal when I plug it directly into the scope, the scope is assumed to be 1M ohm and 20pF but I haven't measured it.This weekend I built a 10 MHz bandpass filter to clean up the signal. A parallel tuned circuit, a series tuned circuit and a second parallel circuit on the output. The capacitors are fixed but the inductors are variable. When I connect the filter between the distribution amplifier and the scope and tune for maximum output I see 6.5V P-P on the scope.Best guess is that the filter is providing a nominal match between the op amp output and the 1M/20pF of the scope input, 20pF is about 796 ohms at 10 MHz. However, the series tuned circuit in the middle uses a 3pF capacitor which is about 5300 ohms at the working frequency so I expected the filter to be lossyWhere is the voltage gain coming from?

author: hagster
author_rank: Frequent Contributor
timestamp: August 24, 2019, 04:20:27 pm
content: No free power here. Reactive circuits can easily have bigger voltages than the input voltage. The power will not have changes(or reduced) therefore the current will be lower

author: David Hess
author_rank: Super Contributor
timestamp: August 24, 2019, 06:37:10 pm
content: Exactly, your bandpass filter is also altering the impedance so the ratio of voltage to current at the output is different.Note that it is tricky to maintain phase coherence with a bandpass filter and especially a complex or high performance one because the phase changes rapidly across the center frequency. One tends to end up with a thermometer which measures temperature using phase. Depending on your accuracy requirements, it might be better to use separate low and high pass filters with notch filters to remove the 2nd and 3rd harmonics.

author: TheUnnamedNewbie
author_rank: Super Contributor
timestamp: August 27, 2019, 04:51:40 am
content: Quote from: hagster on August 24, 2019, 04:20:27 pmI've seen research of people using passive circuits (with transistors, but no external power (or DC bias) applied) that could multiply the voltage on the order of 20 dB or more iirc. Pretty cool stuff.A great device at doing this is a transformer.
Help me choose a Ferrite Material for 500kHz to 4MHz - Page 1
Forum section: electronics / rf-microwave

author: Qmavam
author_rank: Regular Contributor
timestamp: August 24, 2019, 09:45:30 pm
content: I'm looking to make an special inductor.The core I want to use is only available in the materials below.It is low power receive antenna voltages.I have a choice of N87 or N97 from TDK (Epcos)I can't find data sheets for those.And also material 78 from Fair-rite.I just don't know the criteria used to pick the right material for the frequency.Thank you, MikekPS, I have a core that worked for my special purpose, but it ran out at about 300kHz.Meaning, it had good Q until 300kHz and then I could not even get a reading.

author: MarkF
author_rank: Super Contributor
timestamp: August 24, 2019, 10:02:06 pm
content: These may be helpful (Type 2 vs Type 43 cores):

author: Qmavam
author_rank: Regular Contributor
timestamp: August 24, 2019, 10:42:01 pm
content: I did find that interesting, now I want a mini VNA.But I am aware that materials are different, I just don't know what to read in the spec sheets.(if I can find them) to be able to know which material to pick.Thanks, Mikek

author: biastee
author_rank: Regular Contributor
timestamp: August 26, 2019, 02:52:44 am
content: Generally, the upper frequency limit is inversely proportional to the initial permeability. For the specified 0.5-4 MHz range, my TDK catalogue from the 90s indicates that the K5 material (ui = 290) is suitable (fopt <8 MHz).According to the Fair-rite catalogue, material 78's upper freq (<2.5 MHz) is too low for your application.
Weird elevated RF noise floor today? - Page 1
Forum section: electronics / rf-microwave

author: reagle
author_rank: Unknown
timestamp: August 23, 2019, 08:16:38 pm
content: So I happen to have a Rigol DSA815 sitting on my desk. Today I noticed that the usual noise floor of around -80dB is sitting around -55 for as wide of a frequency as I can set the SA for.Checked with another unit- same. A few hours later, noise floor is back down.Any idea if the aliens landed yet, or what else can raise my floor by 25dB across a good 1GHz of spectrum (all under 1.5GHz)?No obvious noise sources nearby, plus I doubt they'd be that wideband..
Holzworth USB Synthesizer Software? - Page 1
Forum section: electronics / rf-microwave

author: DaJMasta
author_rank: Super Contributor
timestamp: September 04, 2019, 11:21:45 pm
content: Got my hands on an older Holzworth Instrumentation HS1001C second hand as a reference for some phase noise measurement stuff, and while the unit seems to be in fine shape, it wasn't shipped with any software. The Holzworth site doesn't have any download links and mentions contacting support for software, but they've been unresponsive (it's been a week and a half or so).Does anyone have the GUI application or a suitable driver for this instrument that they can share? Is there another way to get a hold of the software? Because they don't list previous versions on their site, I haven't even been able to get a full datasheet/user manual for the HS1001C, but there is a promotional flier which lists a lot of relevant specs and the general operation seems like it should be very straight forward.
FEM - RFFM6906 - Page 1
Forum section: electronics / rf-microwave

author: madhu.wesly01
author_rank: Regular Contributor
timestamp: August 21, 2019, 01:27:12 pm
content: Hello,Good day!https://www.qorvo.com/products/p/RFFM6906To use the RFFM6906 - FEM in my application, do I need to connect a Balun at the output of the RFFM6906 to get a 50 ohm single ended output from the LNA or can we take output from ASW_RX pin of RFFM6906 to get a single ended 50 ohm output with LAN output.Can some one tell me what will the pros and cons in both the cases - single ended vs differential pair? How should I operate it at its best?TIA
Vector Impedance Meter - Anything Modern & Inexpensive? - Page 1
Forum section: electronics / rf-microwave

author: NY2KW
author_rank: Regular Contributor
timestamp: August 17, 2019, 04:57:20 pm
content: I have several HF boatanchors that require a vector impedance meter like the old HP 4815A to measure RF filter networks to set phase angle within a specified range for different bands. Getting a HP4815A that works has been difficult. Are there any relatively inexpensive modern substitutes, say < $500 ?Jerry

author: hagster
author_rank: Frequent Contributor
timestamp: August 17, 2019, 05:13:32 pm
content: I recently got a nanoVNA for about £50. Covers 50KHz to 900MHz and seems to work incredibly well. I have used other low cost analysers before and this is the first one I have tried that I could honestly recommend.

author: radiolistener
author_rank: Super Contributor
timestamp: August 18, 2019, 09:32:18 am
content: You can try NanoVNA:https://www.aliexpress.com/item/33016805196.htmlhere is topic about it:https://www.eevblog.com/forum/rf-microwave/nanovna-custom-software/
2.4Ghz constant source signal - Page 1
Forum section: electronics / rf-microwave

author: jacobdel
author_rank: Newbie
timestamp: August 17, 2019, 07:10:05 pm
content: Hi all,It may sound easy but I've been searching the whole internet to make/buy a 2.4ghz continues signal source (up or below doesn't matter, just somewhere in this range). Please note that I'm not searching for a discrete signal source, and with this i mean for example an ESP8266, as this will also send a discrete signal.I found some fragile really old posts, which doesn't seem very reliable:http://rfanat.qrz.ru/s13/SigSourc_2400.htmlhttps://www.qsl.net/yo5ofh/projects/2400mhz_signal/13cm.htmAnother post (https://www.researchgate.net/post/how_to_make_a_24GHz_Microwave_source) recommends to use something like a PLL or VCO and just take it's reference voltage, which is easier said than done because those pins are never accesable, and sending a bunch of empty messages will likely not send the continues 2.4ghz signal i'm looking for .. (because of the same reason I explained for the ESP8266)There is also this product from alixpress:https://www.aliexpress.com/item/32707873441.html?spm=a2g0o.productlist.0.0.6eaf105aXBkoTH&algo_pvid=bb9319f7-9420-4713-8a16-0040d1ad3ac8&algo_expid=bb9319f7-9420-4713-8a16-0040d1ad3ac8-0&btsid=cf54a445-9c11-4138-b5c4-5f716dd3a765&ws_ab_test=searchweb0_0,searchweb201602_9,searchweb201603_60Which seems eh.. a bit untrustworthy?Am I wrong about something or do you have an idea? Please let me knowHave a great day

author: ataradov
author_rank: Super Contributor
timestamp: August 17, 2019, 07:31:52 pm
content: AT86RF233 is the easiest digitally tunable solution that I know of -https://www.microchip.com/wwwproducts/en/AT86RF233.It has CW and PRBS modes.I know people that actually used then in mass produced design and a high frequency clock source.

author: aandrew
author_rank: Frequent Contributor
timestamp: August 18, 2019, 01:35:59 pm
content: Why not just use a $1 nRF24L01 module and configure it via SPI to enable CW? You basically set the RF channel and power level and engage CW. Easy-peasy and cheap.

author: jacobdel
author_rank: Newbie
timestamp: August 20, 2019, 09:03:25 pm
content: Thank you for the answers!Quote from: ataradov on August 17, 2019, 07:31:52 pmThanks for letting me know about this chip! Amazing chip, but there doesn't seem to be a lot of people using it as it's hard to find shops that have them.Do you know another chip with this kind of "phase difference measurement" feature?Quote from: aandrew on August 18, 2019, 01:35:59 pmThanks! Didn't know it could do that.

author: ataradov
author_rank: Super Contributor
timestamp: August 20, 2019, 09:05:42 pm
content: Quote from: jacobdel on August 20, 2019, 09:03:25 pmNo idea. That unit in RF233 is not well documented, so it is not possible to use it without closed library.But the CW generator is very easy to use and I have plenty of code samples for that.
Best way to match PD20010 - Page 1
Forum section: electronics / rf-microwave

author: Radiosonde
author_rank: Contributor
timestamp: August 16, 2019, 03:57:45 pm
content: HelloWhat is the best way to effectively match the in and output of a PD20010 power mosfet?The input is 0,45 +j0,99 and the output is 0,99 +j0,9I calculated the impedances which should be 2.04 Ohms for the input and 3.13 Ohms for the output?!A lowpass matching network calculator shows very small inductance values (in the order of pH).A 10:2 and 2:8 Transformer was also an idea, but it is difficult to find core material for 1,3Ghz.The output power is about 10W.It is very likely that I just failed on calculating something.regards
Transmission Line Calculator - Page 1
Forum section: electronics / rf-microwave

author: ZS6GST
author_rank: Contributor
timestamp: August 15, 2019, 01:50:17 pm
content: I am fascinated by the seeming magic attributes of transmission line stubs in their role as matching transformers, impedance repeaters, resonators, gyrators, attenuators, multiplexers, diplexers, reject and band pass filters, phase snifters and last but not least as able conveyors of signals.As my main interest is in the VHF and UHF bands, coaxial stubs are used when doing simulations using RFSim99 and QUCS while an HP8713 analyzer is used for verification by measurement.The Transmission Line Calculator included with QUCS produces equivalents that embrace the losses and impedance of a defined coaxial stub but it has a limitation as it does not cater for different material for the inner and outer conductors. And there are many coaxial cables that employ different metals for their two conductors.A search on Google turned up an alternative transmission line calculator by AWR but it suffers from the same single choice limitation for inner and outer conductor material.Does anyone know of a TL calculator that allows different inner and outer conductor material?73 Pine

author: radiolistener
author_rank: Super Contributor
timestamp: August 15, 2019, 03:18:11 pm
content: conductor material doesn't matter, you're just needs to take into account impedance of coaxial cable.

author: ZS6GST
author_rank: Contributor
timestamp: August 16, 2019, 01:04:20 pm
content: With coax, the resistivity of conductor material has a small but notable effect on loss.To me this is relevant as I am simulating cavity resonators by using open ended 1/4 wave stubs as equivalent components where mere fractions of change in resistance has a large effect on Q and performance.73 de Pine, ZS6GST
Extremely old Australian Spectrum Analyser - Page 1
Forum section: electronics / rf-microwave

author: comistiontAtiv
author_rank: Newbie
timestamp: August 12, 2019, 12:00:27 pm
content: I was hoping someone might have some stories to share on the pictured Spectrum Analyser. Im guessing it is from the 1950s, and used for testing RCM compliance in Melbourne Australia.Would be nice to get the user manual, bring it back to life.

author: comistiontAtiv
author_rank: Newbie
timestamp: August 12, 2019, 12:08:35 pm
content: PhotosSent from my iPhone using Tapatalk

author: Bud
author_rank: Super Contributor
timestamp: August 12, 2019, 01:07:32 pm
content: Good on you Sir trying to save this beauty

author: PA0PBZ
author_rank: Super Contributor
timestamp: August 12, 2019, 01:17:42 pm
content: It says "Display Unit" so it could be you are missing (part of) the RF part, any big connectors on the back?

author: comistiontAtiv
author_rank: Newbie
timestamp: August 12, 2019, 01:28:43 pm
content: Just some voltage selectors...Sent from my iPhone using Tapatalk

author: PA0PBZ
author_rank: Super Contributor
timestamp: August 12, 2019, 07:34:56 pm
content: Quote from: comistiontAtiv on August 12, 2019, 01:28:43 pmI guess you have the complete package then, which is supported by the RF In connector on the front. Still a bit weird that they labelled it as Display Unit.

author: vk6zgo
author_rank: Super Contributor
timestamp: August 13, 2019, 01:01:56 am
content: I have a feeling that it isn't a Spec An, but more like a sweeper with internal detector & display-----somewhat along the lines of a Polyskop.Or, possibly, a Group Delay tester for microwave links?It definitely would have been from my time working at the PMG's Dept, but, although the whole look of the thing is familiar, I can't quite place it.Most of my time was spent in Radio & TV Broadcasting, rather than Comms, & the time I did spend in that field was mostly HF.

author: comistiontAtiv
author_rank: Newbie
timestamp: August 16, 2019, 01:43:13 pm
content: Thanks all for your repliesSent from my iPhone using Tapatalk
radio astronomy and positional antennas - Page 1
Forum section: electronics / rf-microwave

author: coppercone2
author_rank: Super Contributor
timestamp: August 11, 2019, 12:10:28 am
content: I have played around with making an antenna move, but save for VERY old books (circa1950) from a university library I never saw 'simple' radio astronomy stuff. (That I can see myself building on a reasonable budget).Has anyone done anything like this before? Like sky mapping with whatever parabola or horn or yagi? And meshing software?

author: Gyro
author_rank: Super Contributor
timestamp: August 11, 2019, 10:17:12 am
content: Dipping back into my distant memory, I remember a radio astronomy project series in Practical Electronics Magazine (UK). I remember being fascinated by the antenna designs at the time - it was back in 1971.Volume index here...http://www.the-cool-book-shop.co.uk/practical_electronics/Magazine PDF downloads here:https://www.americanradiohistory.com/Practical_Electronics.htmThe series starts in the June 1971 issue.

author: coppercone2
author_rank: Super Contributor
timestamp: August 11, 2019, 01:20:56 pm
content: wow, people did this once and it died huh?

author: Gyro
author_rank: Super Contributor
timestamp: August 11, 2019, 04:25:14 pm
content: Yep, everything has it's time, radio astronomy was a big thing back then and the space race too of course. If you look back in the archive a couple of years you'll see a lot of radioactivity stuff. Seismographs were popular projects too.These days it's electronic loads.I find it very difficult to go back through those old issues and not get distracted from what I was originally looking for.

author: coppercone2
author_rank: Super Contributor
timestamp: August 11, 2019, 05:33:48 pm
content: I noticed that too, for some reason everyone wants a electronic load and a thermal test chamber.A e-load is kind of like checking your bank account balance, I don't want to look (just hope I can get more in there lol) (in regards to battery life I mean. So what if it only lasts 15 minute??)What can I possibly sacrifice to increase battery life? its engineered perfectly! it just needs more batteries

author: coppercone2
author_rank: Super Contributor
timestamp: August 11, 2019, 05:44:46 pm
content: to be fair, maybe people who like home energy storage and solar can use loads. And they probably make the Chinese shape up with their crappy inverters because people can actually review them with a real test that discourages voo-doo demonstrations which just confuse people with terms like 'reactive' and 'inductive' and 'magnetic'4kW when powering "highly reactive" loads.still have yet to build one, if anything I would make a big heat sink with a bunch of resistors and relays on it lol

author: hfleming
author_rank: Regular Contributor
timestamp: August 13, 2019, 10:25:20 pm
content: Have you had a look here?http://www.radio-astronomy.org/projects

author: coppercone2
author_rank: Super Contributor
timestamp: August 15, 2019, 05:48:24 am
content: i feel a bit paranoid about doing this line of work
Identyfy HV connector type - Page 1
Forum section: electronics / rf-microwave

author: r6502
author_rank: Regular Contributor
timestamp: August 13, 2019, 11:38:29 am
content: Hello all,I have a question regarding a connector type. I uploaded photos of the connector.I found this connector at a high voltage supply for photomultipliers and on NIM modules. It looks like a huge BNC connector. Outer diameter is about 13,5mm (BNC is about 9,7mm).The brand is Amphenol, but I did not find informations on the web side.Does anybody have an idea about the connetor series?Guido

author: ChristofferB
author_rank: Frequent Contributor
timestamp: August 14, 2019, 08:31:58 am
content: I think it's a C connector. They look like giant bnc's, but it looks to be a high voltage variant, with the protruding shield on the chassis connector, just as the mhv connector is to bnc.Be careful, some HV connectors will mate with their non-HV counterparts which is a big safety hazard!--chris
Hardwiring a Somfy 433Mhz radio link - Page 1
Forum section: electronics / rf-microwave

author: smbaker
author_rank: Regular Contributor
timestamp: August 12, 2019, 03:07:08 am
content: I have these Somfy shades in my office that use ~ 433 Mhz to control the shades from an Internet-enabled controller. Three shades, one transmitter. I've already hardwired power to them as replacing 6X lithium AA batteries a couple times a year kinda sucks. The Somfy protocol is one-way without confirmation, occasionally it'll miss a command if there is interference on the 433Mhz band.Lately I started working on a project that uses a 433Mhz FS1000A transmitter/receiver pair, commonly available on eBay for about a buck.Problem is, if the FS1000A transmits at the same time the Somfy transmits, the Somfy signal will not be received. I've built some redundancy into my project and my data will eventually get through, but Somfy didn't build any redundancy into theirs. The command to move the shades is lost.I'm wondering, since I've hardwired power to the Somfy shades anyway, is there a way for me to hardwire RF to them. They don't need to be wireless -- wired is just fine. Perhaps a wire from the transmitter antenna daisy-chained to each receiver, with a capacitor between the wire and the receiver antenna. I just want the Somfy signal to vastly overpower any signal from my FS1000A project. I'm digital projects guy, not an RF guy, so I have no idea what I'm doing ... hence the question.Thanks,Scott
Pryme BT-PTT receiver? - Page 1
Forum section: electronics / rf-microwave

author: 1sciguy
author_rank: Contributor
timestamp: August 08, 2019, 03:52:55 pm
content: I'm working on a paramotor headset and I want to implement a wireless Push-to-talk button to my ICOM radio. It would be easiest if I could take an off-the-shelf solution that is already battle proven. I noticed the Pryme BT-PTT-Z is a nice rugged button and it apparently doesn't need to be recharged. I am assuming it must have a permanent battery that lasts for years.. Does anyone know its communication standard? Is it low power bluetooth? Would there be a chip receiver out there somewhere that I can interface to a PIC microcontroller, or better yet something stand alone that will cause a contact closure when the remote button is pressed? If there are any other ideas out there, I'm all ears..Thanks!

author: 1sciguy
author_rank: Contributor
timestamp: August 08, 2019, 05:53:32 pm
content: Answering my own question.. It is definitely bluetooth. Seems like the simplest solution is a 433Mhz keyfob and receiver for $6 off ebay.
How to implement CW (OOK) with ADF4351 - Page 1
Forum section: electronics / rf-microwave

author: Radiosonde
author_rank: Contributor
timestamp: August 03, 2019, 05:18:53 pm
content: HelloRight now I am waiting for the parts and pcbs for my EsHail transverter, so it is time to at least start to start a new project:)I plan to build a simple 23cm beacon for our local repeater site.So, what is the best way to modulate the signal of an ADF4351?Right now I just need CW for the call and maybe temperature, but how to do it?An IQ modulator IC seems a bit complicated, i havent found anything on how to implement an IQ data generator with atmega?!Is it a good idea to "modulate" it via a voltage controlled attenuator, this seems a little bit "dirty" to me.73

author: PA0PBZ
author_rank: Super Contributor
timestamp: August 03, 2019, 05:32:45 pm
content: From the datasheet: Pin 26, RF Power-Down, A logic low on this pin mutes the RF outputs.

author: CJay
author_rank: Super Contributor
timestamp: August 05, 2019, 12:02:53 pm
content: Or indeed with the power down bit in R2

author: Radiosonde
author_rank: Contributor
timestamp: August 07, 2019, 10:00:53 am
content: HelloThnak you for the answers, but, that doesnt quite help because I also need a tone to be modulated onto the signal, otherwise it would just be the carrier.I came up with an aproach myself: 2khz Tone from MCU->Filter->SA612->Filter->LT5560 ....The SA612 and the ADF4351 as LO for the LT5560 are using the same 10Mhz 0.2ppm TCXO.I build it up manhattan style and it works so farthank you for your replies

author: CJay
author_rank: Super Contributor
timestamp: August 07, 2019, 10:46:48 am
content: Ah, right, so it's not just OOK you needed.

author: PA0PBZ
author_rank: Super Contributor
timestamp: August 07, 2019, 11:36:06 am
content: Yeah, that's not CW but MCW

author: CJay
author_rank: Super Contributor
timestamp: August 07, 2019, 12:10:29 pm
content: It would be nice to see how it turns out as a project, I'm waiting for some LT IQ modulators to arrive and use with the ADF4351 for SSB on QO-100, I've decided, for now, to use a Teensy 3.6 to deal with creating the I/Q signals, the Audio library is excellent and (important for me) easy to use.
connector's scattering parameters - Page 1
Forum section: electronics / rf-microwave

author: RFbeginner
author_rank: Newbie
timestamp: August 14, 2019, 08:00:12 pm
content: Hello everyone,I am desperately trying to find the Scattering parameters of a connector. For that purpose, I designed two lines, one of length L and the other of length 2L.First idea was to use the T parameters to find the connector’s S parameters and the idea was as follow:Tmeasured_L = Tc Tline TcTmeasured_2L = Tc Tline Tline TcAnd then:  * -1= Tc Tline Tc-1= Ta-1 * Ta = Tc-1Tc-1and then invert everything and square root… this is the matlab code but the result cannot be correctCode:%% S ParametersDataL = read(rfdata.data,'S2P-L.s2p');Data2L = read(rfdata.data,'S2P-2L.s2p');freq = DataL.Freq;SPL = extract(DataL, 'S_PARAMETERS',50);SP2L = extract(Data2L, 'S_PARAMETERS',50);%% S to TTPL = s2t(SPL);TP2L = s2t(SP2L);%% sizesize(TPL)length(TPL(2,2,:))%%for i=1:length(TPL(2,2,:))TA(:,:,i)=TP2L(:,:,i)/TPL(:,:,i);TB_1(:,:,i) = TPL(:,:,i)\TA(:,:,i);TB(:,:,i) = inv(TB_1(:,:,i));TC(:,:,i)=sqrtm(TB(:,:,i));endSC = t2s(TC);so next idea was to try and find every parameter at a time and I already determined the complex propagation constant, both alpha and beta and seems ok but kinda lost on how to find S11 and S22.Any ideas?thanks

author: Simon
author_rank: Unknown
timestamp: August 15, 2019, 11:51:41 am
content: Please do not double post, it does not make you very popular.....
Manage the PTT from the Sound Modem? - Page 1
Forum section: electronics / rf-microwave

author: Lord of nothing
author_rank: Super Contributor
timestamp: August 03, 2019, 09:53:46 am
content: HiI currently use 3 different Software to transmit Sound via an Sound Modem.Is there an Software who allow to use all 3 (sepperated)?So the must create 3 Virtual Com Ports for the PTT.I use the Yaesu SCU-17 for CB.Thanks
Anritsu MG3670B signal generator repair - Page 1
Forum section: electronics / rf-microwave

author: feedback.loop
author_rank: Frequent Contributor
timestamp: June 23, 2019, 03:14:10 am
content: Hi everyone!I am trying to repair an Anritsu MG3670B signal generator. Can anyone share schematic?Thank you.

author: feedback.loop
author_rank: Frequent Contributor
timestamp: July 28, 2019, 11:04:45 pm
content: Finally I got around to this repair and made a lot of progress. A couple of problems have been found and fixed. Now the generator produces output of the right frequency and level. There is still something wrong with modulation extension modules. The generator does not boot up if the extensions are installed.I would appreciate a service manual. I had to manage without so far.

author: German_EE
author_rank: Super Contributor
timestamp: August 02, 2019, 08:50:09 pm
content: There is some nice logical fault finding in that video, good luck with the PCBs!