hybridfree/eevblog-posts huggingface dataset:
Rohde & Schwarz NGE100 / LCD replace - Page 1
Forum section: electronics / repair

author: 3apw
author_rank: Contributor
timestamp: August 26, 2022, 05:18:52 pm
content: Hello All,does anyone know the type (name) of 3.5" LCD module (320 x 240 pixels) of R&S NGE100 power supply?I need to replace this LCD module after mechanical damage.R&S LCD part number is 3625.7378.00Karen, ra3apw

author: thm_w
author_rank: Super Contributor
timestamp: August 26, 2022, 09:45:41 pm
content: Did you take it out to see if there are any markings on it?Whats the price from R&S?

author: 3apw
author_rank: Contributor
timestamp: August 27, 2022, 09:11:44 am
content: Quote from: thm_w on August 26, 2022, 09:45:41 pmNot yet.Quote from: thm_w on August 26, 2022, 09:45:41 pmAbout 200 EUR according a non-official preliminary answer.

author: YetAnotherTechie
author_rank: Regular Contributor
timestamp: August 30, 2022, 01:26:45 am
content: Here...

author: 3apw
author_rank: Contributor
timestamp: August 30, 2022, 07:00:41 am
content: Quote from: YetAnotherTechie on August 30, 2022, 01:26:45 amYetAnotherTechie, thanks a lot.Do you have any details about LCD's interface and controller chip?

author: Mark S
author_rank: Newbie
timestamp: August 30, 2022, 09:11:40 am
content: I got a similar LCD direct from R&S for 70 Euros if my memory serves me correctly.Go to R&S website and submit a support request.73s Mark S=

author: 3apw
author_rank: Contributor
timestamp: August 30, 2022, 09:27:06 am
content: Quote from: Mark S on August 30, 2022, 09:11:40 amMark, thank you. Good price.I did it yesterday direct to R&S CustomerSupport team.73 de Karen, ra3apw

author: YetAnotherTechie
author_rank: Regular Contributor
timestamp: August 30, 2022, 03:16:34 pm
content: Quote from: 3apw on August 30, 2022, 07:00:41 amMight be a variation of et0350 but i'm not certain.

author: 3apw
author_rank: Contributor
timestamp: August 30, 2022, 05:24:15 pm
content: Quote from: YetAnotherTechie on August 30, 2022, 03:16:34 pmThank you.It seems it can be close tohttps://www.lcd-mikroelektronik.de/images/stories/virtuemart/product/Drawing_YTS350ELAV-01-100N.pdfWill wait an official R&S answer...
Rohde & Schwarz NGE100 Power Supply  - Page 1
Forum section: electronics / repair

author: Scutarius
author_rank: Regular Contributor
timestamp: August 24, 2022, 02:40:35 pm
content: Hi,I have a power supply with both channels blew up, Dave's teardown has a good capture of the areahttps://youtu.be/Z6F7Pwi6WLI?t=1174What it looks to be the current sense resistor is totally damaged, does anyone here can confirm that it is a R050 metal foil resistor?I can barely read the marksR050 FL4344Any suggestions on the tolerance, 0.1%? Is the green material always an indication of a metal foil resistor?Thanks,

author: thm_w
author_rank: Super Contributor
timestamp: August 25, 2022, 11:27:52 pm
content: R050 FH204R (unsure about the 4)Can you measure the package size to help narrow it down.Metal foil.F might be 1%:https://www.yageo.com/upload/media/product/productsearch/datasheet/rchip/PYu-PE_521_RoHS_L_10.pdf

author: Scutarius
author_rank: Regular Contributor
timestamp: August 26, 2022, 01:36:18 pm
content: Hi thanks!it is ~3.15x6.3 mm

author: thm_w
author_rank: Super Contributor
timestamp: August 26, 2022, 10:01:56 pm
content: Thats 2512 package (0.25"x0.12").If you can't find the exact part, there is a ohmite 0.5% 50ppm for $1.50 on digikey (PCS2512DR0500ET).Would expect thats good enough.Next question is how to recalibrate the current readings.

author: Scutarius
author_rank: Regular Contributor
timestamp: August 29, 2022, 01:55:18 pm
content: Thanksand assuming this no other damaged component...
Rohde & Schwarz NGPS 40 - service manual - Page 1
Forum section: electronics / repair

author: koenver
author_rank: Newbie
timestamp: December 26, 2016, 11:01:16 am
content: Hello,Does some body has a (service) manual of the Rohde & Schwarz NGPS (-40/+40V 0.1A) programmable voltage source ("Steuerspannungsquelle" is written on the machine) ? NGPS series 192.0061.02greetingsKoen VerstappenNetherlands

author: tonyalbus
author_rank: Super Contributor
timestamp: December 23, 2021, 04:14:09 pm
content: Hallo Koen, did you even found this manual?i am looking for it now, it would be a great help.Tony

author: Qw3rtzuiop
author_rank: Frequent Contributor
timestamp: December 24, 2021, 02:20:50 pm
content: This guy sells the the manual:http://www.rainer-foertig.de/unterlagen/RS-16_2010.htm

author: 240RS
author_rank: Regular Contributor
timestamp: May 05, 2023, 10:18:11 am
content: Mailed the latter. Tony, you have an NGPS?
Rohde & Schwarz R&S HMC804x NGC10x Power Supply Repair  - Page 1
Forum section: electronics / repair

author: RoadRunner
author_rank: Frequent Contributor
timestamp: January 11, 2025, 05:47:33 pm
content: I was having a broken HMC8042 with me, Somehow managed to Repair. Here is a video describing.I have figured out communication Protocol between Main CPU and Individual Channels as well.

author: pdenisowski
author_rank: Super Contributor
timestamp: January 13, 2025, 03:14:56 pm
content: Impressive!

author: RoadRunner
author_rank: Frequent Contributor
timestamp: January 13, 2025, 10:40:54 pm
content: Quote from: pdenisowski on January 13, 2025, 03:14:56 pmThank you.
Rohde & Schwarz RTM 1052 Help - Page 1
Forum section: electronics / repair

author: sprit
author_rank: Regular Contributor
timestamp: September 04, 2024, 03:36:03 am
content: Hello everyone. Have a good day. I just found an RTM 1052 with a broken screen on the second hand market. After bringing it home and connected to external monitor, it shows error as above. Upon inspection I found some solder marks in input area, and probe is not working. I have searched for its service manual but failed. Can anyone help me? Thanks for your kind help.SincerelyFeng

author: tooki
author_rank: Super Contributor
timestamp: September 04, 2024, 06:37:24 pm
content: 1. Please don't override the default font unless there is a REALLY important reason to do so. No such reason exists here.2. You did not provide the error. We can't help without that!3. There's a great R&S representative on here who's often super-helpful. Maybe he can get a service manual?@pdenisowskican you take a look?
Rohde & Schwarz RTO1024 Oscilloscope is broken, i need help - Page 1
Forum section: electronics / repair

author: myhobo
author_rank: Regular Contributor
timestamp: April 04, 2019, 02:14:52 am
content: I need the program file of this EEPRPOM, can anyone help me copy the program file of this chip, thank you

author: myhobo
author_rank: Regular Contributor
timestamp: April 05, 2019, 02:39:24 pm
content: who can help me

author: myhobo
author_rank: Regular Contributor
timestamp: April 05, 2019, 02:40:24 pm
content: who have this oscilloscope serve manual

author: perdrix
author_rank: Frequent Contributor
timestamp: April 06, 2019, 02:26:32 am
content: You should be a little patient, chasing for replies after such a short time will not get you help faster.Wait a day or two.David

author: myhobo
author_rank: Regular Contributor
timestamp: April 07, 2019, 01:14:05 am
content: thanks perdrix

author: TRN
author_rank: Unknown
timestamp: May 02, 2019, 05:45:43 pm
content: Hi,First run a self test, then run the internal alignment test, and upload the error log so the forum members can have a look at it.My first guess is that the VarGain 50 and FixGain 50 errors from the self-alignment test probably indicate that there is an issue with the gain of the Variable gain amplifiers in the analog front-end.To check this you should Inject an AC signal into the BNC inputs of channels 3 & 4 and measure the amplitude at the input of the ADC's from the same channels. Verifying these against the signal amplitudes of channels 1 & 2 should give you an idea if the variable gain amplifiers are suspect.regards

author: myhobo
author_rank: Regular Contributor
timestamp: December 09, 2019, 12:20:45 pm
content: My RTO1024 oscilloscope bios chip program is broken, the machine cannot start, can anyone help me copy the content of this chip, thank you

author: myhobo
author_rank: Regular Contributor
timestamp: December 09, 2019, 12:24:44 pm
content: I need the program file of this EEPRPOM, can anyone help me copy the program file of this chip, thank you
rohde schwarz SMHU block diagram, service ? doubler - Page 1
Forum section: electronics / repair

author: oz2cpu
author_rank: Frequent Contributor
timestamp: August 07, 2025, 03:00:48 pm
content: I just scored a nice looking Rohde & Schwarz SMHU free gift to my youtube channel,so I am super happy about it,ofcourse it is defective, but super luck i just touched one of the SMA connectors from the douplerit was broken, so i soldered it in , and BINGO i now have output,may happiness came to a stop when i realized i got good output 1MHz to 2100 MHzand zero output 2200MHz and up, so clearly it apear like the doupler if not workingor it selection system, filter selevt, rf path switching, many things can actually give this outcome.so here you come in .. I cant even find a signal path block diagram, for this section,no service manuals, no schematics,please help ??

author: oz2cpu
author_rank: Frequent Contributor
timestamp: August 07, 2025, 08:24:00 pm
content: more news.. not zero output, but over 30dB too low, when doubler is activated,I tried a few measurements via the SMA connectors to modulesI feel the output from the doubler is way too lowit is cheramic and bond wire design, so close to impossible to repair
Rohde Schwarz SML 02 RF Signal Generator repair - Page 1
Forum section: electronics / repair

author: hcglitte
author_rank: Regular Contributor
timestamp: January 13, 2022, 03:36:03 pm
content: Hi,I got a SML 02 sig gen which fails during calibration.It fails at MULT-FILTER OPU3.I have the service manuals, part 1 & 2. But no schematic.Level preset also fails, but may be dependent on OPU3 multiplier filter.It seems that OPU3 is used for higher frequencies only, hence using only lower frequencies may bypass it, if it is not fixable.It does give RF out, but at wrong level.Some lines at LCD, but that is OK.Anyone who have experienced the same problem, or got some tips?
ROHDE & SCHWARZ SML01/02/03 SG ATTENUATOR Repairs - Page 1
Forum section: electronics / repair

author: shashitej
author_rank: Contributor
timestamp: April 01, 2023, 08:25:30 am
content: Hello ALL,This is my first post on this blog, knowingly or unknowingly if I make a mistake pls help me to rectify itI have got Rohde & Schwarz SML03 Signal Generators - 3nos with problemsone of the problem is horizontal lines on the displays ->LCD's to be replacedsecond problem is all the 3 attenuators behaving erratically like,(1) at 0 dbm output is -17dbm, in one module,(2) at 0dbm working fine but on negative side behaving erratically like-7dbm=-24dbm, -22dbm=-50 dbm so on 2nd module(3) difference of -12 to -15 dbm at all levels 3rd moduledoes anyone have the component layout and schematics for this attenuator module or where can i purchase the sameThe module consists of GaAs MMIC SPDT RF switchesAny help is highly appreciated .

author: Brandy
author_rank: Newbie
timestamp: February 01, 2024, 01:08:09 pm
content: Most likely it's the little white smd parts, which are "P35-4227-C06-300" high performance Gallium Arsenide single pole double throw broadband RF switches.I have the same problem, my device makes jumps in 5dB steps, depending on the attenuation settings.You may shorten the required pins and see if it helps. Surely you will skip the steps of the shorted witch.See the attachment for the switches.Unfortunately it seems that the parts are not available anymore, at least I cannot find them in the net...Maybe you can take them from another SML as you have more than one

author: ardiesse
author_rank: Newbie
timestamp: February 01, 2024, 11:51:56 pm
content: You can identify which switches are at fault using a multimeter.Take the shields off the attenuator, and temporarily re-install the attenuator in position without shields. Turn the signal generator on and probe switch pins 6 and 7 with a multimeter, as you vary the output level (1 dB steps are handy).Normal voltages at pins 6 and 7 are about +1.0 V "high" and about -7 V "low". When a switch goes bad the voltage swing at pins 6 and 7 is much less. Start troubleshooting from the RF input and follow the PC traces through to the output. You don't need schematics.That's how to troubleshoot the bad switches. Replacement is a different matter. I'm using SSW124 as replacements, but these are old lab stock. I don't know whether anybody makes pin-compatible replacements. The Mini-Circuits KSWA-2-46 has a different pinout.Rob
Rohde & Schwarz SML03 "Error 110 - Output Unleveled OPU3" - Page 1
Forum section: electronics / repair

author: TexasTest
author_rank: Newbie
timestamp: January 17, 2022, 02:28:04 am
content: I purchased 5 of these at auction for a very good price but they get the following error above 1.1G: "Error 110 _ Output unleveled OPU3".ALL 5 with the same error! Any Ideas?Surely they don't all have the same exact issue? Or is this common with this model?If so I guess it works fine as an SML01 but I would like to get them working at 3.3g!!Any Ideas??
Rohde & Schwarz UDL 45 Digital Multimeter - need help to find schematics... - Page 1
Forum section: electronics / repair

author: carl_lab
author_rank: Frequent Contributor
timestamp: February 18, 2019, 03:09:21 pm
content: Can somebody help me to find schematics for a Rohde & Schwarz UDL 45 Digital Multimeter?I've used google search, but this multimeter seems to be non-existent at the web...

author: coromonadalix
author_rank: Super Contributor
timestamp: February 19, 2019, 12:35:41 am
content: The only one ive found is the model 44 pictures, nothing else ?? does your has some ressemblance ??

author: carl_lab
author_rank: Frequent Contributor
timestamp: February 19, 2019, 11:55:12 am
content: The 45 is completely different to the 44:

author: tmlab
author_rank: Newbie
timestamp: May 02, 2019, 10:34:36 am
content: Take a look at this thread:https://www.eevblog.com/forum/testgear/analogic-data-precision-dp100-5-5-digit-mulimeter/It's from another brand but it's the same as your

author: carl_lab
author_rank: Frequent Contributor
timestamp: May 20, 2019, 09:38:31 am
content: Thank you, this one looks nearly identical.Can anybody explain how to reassemble multi-part archive files fromhttp://www.eserviceinfo.com/download.php?fileid=62715

author: Chris56000
author_rank: Frequent Contributor
timestamp: May 20, 2019, 06:44:20 pm
content: Hi!The files are complete in themselves and only need to be downloaded from the eservice info website, then they can be printed out separately and then put together manually – unfortunately I don't think that applications that will merge the six dp100 pdf files are free!Chris Williams

author: carl_lab
author_rank: Frequent Contributor
timestamp: May 21, 2019, 06:26:19 am
content: Chris, you're right, these are single PDF files...Here's a nice, free PDF printing and manipulating tool, I'm still using for a while:https://translate.google.de/translate?hl=de&tab=wT&sl=auto&tl=en&u=https%3A%2F%2Fwww.heise.de%2Fdownload%2Fproduct%2Fpdf24-creator-36252

author: Zeitkind
author_rank: Contributor
timestamp: October 07, 2021, 01:16:18 pm
content: @coromonadalixYeah, it's an old thread, but just FYI, the Rohde und Schwarz Digital Multimeter UDL 44 is a rebranded SOAR 5430. Same or related models were also sold as Yokogawa 7541 & 7542, Panasonic / National Digital Multimeter VP-2662A and prob. some more. They do have some different options and features, also precision may vary, like mV/V ~ 0,07% to 0,04% ±2 depending on model. They were sold in the late 80s and did not cost a bargain, but nevertheless great price for what they offered. I still use the "original" SOAR 5430 on a more or less daily basis and it still bang on - which is great for a ~30 years old "24999" multimeter.From the online database @electronicsandbooks.com, the SOAR 5430 has:Range Stability Low High Resolution 1yDC Volt 250m 1k 10u 400AC Volt 250m 750 10u 5000 Max Frequency 10kResistance 250 250M 10m 600DC Current 250m 10 10u 3000AC Current 250m 10 10u 7500It's kinda sad, that SOAR vanished later, they had great products for the price. Does anyone know why they gave up?
Rohde Schwarz UPD, service manual needed - Page 1
Forum section: electronics / repair

author: Aheld
author_rank: Regular Contributor
timestamp: September 25, 2022, 09:16:02 am
content: Hi Forum,My R&S UPD starts with some issues.I think I need to change a lot of Elkos.I there any on who can help me with the service manual(s)?Thank youAxel
Rohde Schwarz UPD service manual - Page 1
Forum section: electronics / repair

author: Andrejka
author_rank: Contributor
timestamp: August 27, 2024, 05:25:40 am
content: Hello community,Looking for service manual for Tohde Schwarz UPD audio analyzer.Many ThanksAndrej

author: Harry_22
author_rank: Frequent Contributor
timestamp: August 27, 2024, 08:03:24 am
content: Hi Andrej!Please let me know what exact sections do you need.I will try to make you a copy.

author: krucker
author_rank: Newbie
timestamp: August 27, 2024, 02:50:01 pm
content: HelloI hope this will help you. Sorry, no schematics.Gerhard

author: krucker
author_rank: Newbie
timestamp: August 27, 2024, 02:52:15 pm
content: Here is the attachment...

author: Andrejka
author_rank: Contributor
timestamp: August 29, 2024, 05:15:05 am
content: Hello,Big Thanks forkruckerandHarry_22!Manual will be very helpful to restore my UPD analyzer. If Vol2 with the schematics can be available, I will be very appreciate if someone attach it here.Many ThanksAndrej

author: Aheld
author_rank: Regular Contributor
timestamp: August 30, 2024, 09:12:44 am
content: Did you check out this discussion:https://www.diyaudio.com/community/threads/rohde-schwarz-upd-help-need-docs-files-repair-advice.286032/page-5They're talking about damaged AC filter at UPD devices?Maybe a hint for the not working PSU?Br.Axel

author: Astralix
author_rank: Regular Contributor
timestamp: September 02, 2024, 11:52:41 am
content: Hi!Thank you Harry for the support, but is there a Volume 2 available too?The units will probably now be at the age, were caps liquids are string to eat away traces and through-holes and in my case the battery leaked and the two spacer rubber things became some gluey liquid stuff that dropped down into the ISA slots of the PC mainboard.So being able to trace some signals on schematics level would really help!Best regardsastralix

author: frozenfrogz
author_rank: Frequent Contributor
timestamp: March 26, 2025, 09:45:21 am
content: Sorry to necro this thread, but I thought it to be the most fitting option..I would also be veryinterested in Vol.2 of the UPD service manual.I have Vol.1 & Vol.2 of the UPL service manual if that is of interest to someone else.Also: Does anyone know about the procedure to install software options on the UPD? I might have a matching key for the B22 Jitter Option on my UPD, but no idea where to put it. Installing software Options is different on the UPL.The newest version of the UPD operating manual has a chapter on installing the B22 option as per user, but there is only the headline of the section without any further procedure description. xDIf anyone still has an install disk or paper trail for this, I would be grateful!
Rohde & Schwarz URE 2 Voltmeter - DC range not working - Page 1
Forum section: electronics / repair

author: exor
author_rank: Regular Contributor
timestamp: September 09, 2020, 09:32:10 pm
content: I was about to buy a second hand URE 2 RMS Voltmeter and went to pick it up. Seller said that he has an Agilent 33220A we can use to test the meter so I took only my Burster DC source with me.With the function generator everything looked nice and I was ready to shake hand (not literally in these days) but wanted to check quickly the DC range. And good I did as it didn’t work, only some digits at lowest range. I checked all settings, changed range up and down and initialised the URE but anything didn’t help. It passes self test at power on and don’t have any alarms.Maybe there is some relay for bypass input capacitor and it is not working or has bad contact? If fault is relative easy to find and fix I might buy it at some lower price but it is not worth to take it to R&S for repair.I wonder if someone here has URE 2 schematic or better yet service manual? URE 3 will do also, should be quite similar.

author: George Edmonds
author_rank: Frequent Contributor
timestamp: September 10, 2020, 04:50:22 am
content: HiThis maybe usefulhttps://elektrotanya.com/rohde_schwarz_ure_rms_voltmeter_sm.pdf/download.html#dlIt does include schematics.George G6HIG
Rohde Schwarz URV5 E200 error - Page 1
Forum section: electronics / repair

author: Nevada
author_rank: Contributor
timestamp: November 21, 2021, 06:11:28 pm
content: Hi,I have a R&S URV5 which indicates E200 error code. The manual says it is an offset problem, but there is no other details given. Could somebody give a suggestion, or know the problem?
Rohde & Schwarz URV5-Z7 probe - Page 1
Forum section: electronics / repair

author: Nevada
author_rank: Contributor
timestamp: November 05, 2021, 02:14:08 pm
content: Hello,I've got a R&S URV5-Z7 probe, but some parts are missing from inside unfortunately. I assume it feeded with higher voltage than spec'd. Could somebody show a photo about the input section, how the tip is connected to the input cap and two diodes?
Rohde Schwarz  ZVCE NT disk image needed - Page 1
Forum section: electronics / repair

author: Jarek
author_rank: Regular Contributor
timestamp: May 09, 2023, 11:50:02 pm
content: HelloDoes anyone have a disk image of ZVCE NT version?I only have the dos version.

author: coromonadalix
author_rank: Super Contributor
timestamp: May 10, 2023, 12:04:15 am
content: maybe something in this threadhttps://www.eevblog.com/forum/repair/rohde-schwarz-zvr-vna-repair/msg2891896/#msg2891896reply #62 ??https://www.dropbox.com/s/95ggozdptolvj13/zvce.zip?dl=0&file_subpath=%2Fzvce

author: Jarek
author_rank: Regular Contributor
timestamp: May 10, 2023, 12:45:49 am
content: Thank you for your answer . The version from the link is DOS. I need it on NT.Regards

author: Jarek
author_rank: Regular Contributor
timestamp: May 12, 2023, 10:54:08 pm
content: Problem solved topic to close.

author: pmx
author_rank: Contributor
timestamp: August 08, 2025, 09:09:06 pm
content: Hi Jarek,I've one question for your, as you solved your problem :I've a R&S ZVR (NT version), same familly than the ZVCE.So you can use a disk image from another unit without problem ?BTW, is thers some factory calibration files somewhere ? (Like my LeCroy scope)

author: Jarek
author_rank: Regular Contributor
timestamp: August 09, 2025, 08:39:34 am
content: Hi PMXI managed to clone my original disk.
Rohde Schwarz ZVCE  VNA repair  - Page 1
Forum section: electronics / repair

author: Jarek
author_rank: Regular Contributor
timestamp: May 15, 2023, 09:22:39 am
content: HelloI need help identifying the components on the A160 OUTPUT STAGE vna board.There may also be a diagram of this board please.Now there is a total of about 650 ohm resistance.A photo of the place can help too.

author: Jarek
author_rank: Regular Contributor
timestamp: July 04, 2023, 10:41:31 pm
content: HiI have a problem with ZVCE.the problem is with channel b1.One of the photos is the correct signal from the service manual. Unfortunately, mine is different. Has anyone repaired something like this?
ROHDE SML-02 over ERROR - Page 1
Forum section: electronics / repair

author: hnjmkl
author_rank: Regular Contributor
timestamp: April 20, 2022, 07:56:24 pm
content: I don't know if this is a problem or defect of my new purchase, setting 13 dBm gives them from 6 MHz up to 2.2GHz, from 5 MHZ-9 KHz, over 11 dBm from over error.

author: Qw3rtzuiop
author_rank: Frequent Contributor
timestamp: April 21, 2022, 05:22:13 am
content: Don't know if I got your fault description right but you can set a higher than specified output level on the device.The specification is 11dBm max for the SML at frequencies above 5MHz.If you set a higher level you get a warning message like level over range or something similar

author: hnjmkl
author_rank: Regular Contributor
timestamp: April 21, 2022, 11:58:41 am
content: Due to my n inability I was able to locate the 11 dBm limitation in the SML-02 datasheet
Rohde&Schwarz RTB2004 schematic diagram - Page 1
Forum section: electronics / repair

author: Sogra
author_rank: Newbie
timestamp: February 15, 2022, 08:26:40 pm
content: Hi folks.I have a broken Rohde&Schwarz RTB2004 scope and try to repair it.Unfortunately, the Service Manual that I've found is not detailed and doesn't contain a schematic diagram.Is there any chance that somebody here has it ? If you have, please share it with me.Thanks in advance !
Rokit KRK again! - Page 1
Forum section: electronics / repair

author: Wudzi
author_rank: Newbie
timestamp: December 21, 2019, 12:24:52 pm
content: Hi all,I have 2 KRK 6's that have been in storage for a few years. Just fired them up and one is working but the other has no output on the woofer. The tweeter is OK.I've tried to scrape of the blank gunk as best as I can but I'm not sure if the problem is related or not. What I've found is that the resistance between the + and - on the woofer outputs is consistently 2.5m on the good one. However on the bad one, each time I touch the probes against the outputs it changes from about 30k to 2.5m alternating each time.I suspected the main caps (the 3300uf and 1000uf ones) but with those removed, the behaviour is the same.It very strange, I can only think the small voltage from the probe is changing something.The fault is definitely on the power board as the rest of the speaker works fine with the known good board swapped in.thanks
Amp Input goes microphonic?    Solved - Page 1
Forum section: electronics / repair

author: Zero_Ego
author_rank: Regular Contributor
timestamp: April 23, 2025, 03:31:28 am
content: Hi,UPDATE: Fixed. It was user error. Thank you.I was hoping someone might take a look at this 03:22 (REMOVED) minute video demonstrating strange Input Jack/Cable behavior amplifier please?It show's what I am calling - 'microphonic behavior' when I plug in a simple cable into the input jack.It does not matter what type of cable however XLR to 1/4" are it hates with a passion.No microphone necessary? (Turns out this is normal)Attached: Input Board Schematic (Below)What is happening electronically to the input of this unit? Can someone explain it in simple layman's terms.How does BOTH, the outer shield - normally the ground - and the inner tip of the cable become an audible signal. Its like an electronic loop without feed back. (Layman what can I do?)Could a shorted cap cause this problem?I would love any advice on if this can be fixed because I can't have this noise in when I plug in my guitar. I want a nice clean signal.Thank you for readingZE

author: cte
author_rank: Regular Contributor
timestamp: April 23, 2025, 01:52:25 pm
content: Your video is set to "private" and can not be viewed.

author: themadhippy
author_rank: Super Contributor
timestamp: April 23, 2025, 04:04:18 pm
content: Quotecables is acting as a capacitor,normally it is only an issue with high impedance circuits.

author: Zero_Ego
author_rank: Regular Contributor
timestamp: April 24, 2025, 05:41:24 am
content: Thanks everyone for replying.This is somewhat of an embarrassing update but hey we all make mistakes and I did learn something reading your comments - so I thank you very much.UPDATE: I have found it was a bad cable or the wiring in my Shure 565SD (Original USA MADE) (I switched microphones and it worked fine)I'm not sure how to test the pinouts on my Shure 565SD. I may have replace the plug and wired it wrong. (I'm no XLR expert)It could also be a faulty cable you are seeing out of the box from Jaycar. (But highly unlikely) I am still tying to get to the bottom of this.I'm pretty embarrassed for making such a rookie blunder. It can throw you and you start to question everything you know. What you are seeing in this video - is a moron massaging probably perfectly good audio cables believing that he has some "mysterious" fault.The only mystery is the number of my brain cells?Thanks.Please see EEVBLOG for more of my antics -good and sad. (Boo get off)What makes this double embarresing is that I thought I removed it. I clicked the remove button in the top right corner. Clearly that is the wrong button.My shock when I saw my inbow today. Pretty funy. All I'm doing is messing with possibly pefectly good audio cables and stating that they are microphonic. I guess in a sense - that open mic cable - when amplified is acting micophonic - yes/no?

author: Zero_Ego
author_rank: Regular Contributor
timestamp: April 24, 2025, 05:48:30 am
content: You guys were onto this without my video. That's some skill.Well done.This is a classic case of ID10T error.
Roland E70 1990'd Synth - stuck at Test mode - Page 1
Forum section: electronics / repair

author: chirath22
author_rank: Newbie
timestamp: July 05, 2025, 04:37:03 am
content: Hello everyone.I got an old E70 synth for repair, and when I switch it on, it directly goes to test mode. Even when I disconnect the panel connector, it's the same. Also, when I disconnect the GSC PCB, it's still the same.How can I rectify this issue? I believe the firmware may be damaged. Please helpThank youChirath

author: darkspr1te
author_rank: Frequent Contributor
timestamp: July 05, 2025, 09:51:52 am
content: I had a quick look at the service manual and noted it requires menu to be held when powered on, might be worth tracing that pin to the mcu to see if it's held down for any reason, failed resistor, menu key stuck, failed pull up/downhttps://www.synthxl.com/roland-e-70/
Roland Jupiter 6 freezing when trying to access memory locations - Page 1
Forum section: electronics / repair

author: belzrebuth
author_rank: Frequent Contributor
timestamp: October 04, 2024, 04:24:12 pm
content: Hi all,I've got a Jupiter 6 synthesizer that needs some attention.It had a flat battery so it must have had all of its sounds erased but it seems to be more than this at play here.I tried restoring the original patches via tape but the process never finishes, this is a quite daunting task with this synth but I don't think this is actually my problem.When I sent the patch data thru the tape interface all LEDs light up sequentially but the procedure does not end with LEDs A and 1 lit as it should so it might actually be a verification issue.There is actual patch data on some locations but the synth randomly freezes with I'm trying to access different patches.Here is a clean copy of the service manual with schematics (page 13 is the digital section):https://www.florian-anwander.de/roland_jp6/Roland_Jupiter-6_Service.pdfI'm not sure on where to start with this other than replacing the "tone ram" IC24 and maybe IC18 and IC19 which are responsible for read and write(?)I'd appreciate some help on what I should look out for..
Roland keyboard - Page 1
Forum section: electronics / repair

author: woodchips
author_rank: Frequent Contributor
timestamp: May 28, 2019, 07:10:50 pm
content: Just repaired a Roland keyboard, can't remember the number, given it back!Problem was one note wouldn't sound. This keyboard is fairly old but the keys are velocity sensitive, so hot harder, louder noise.With the keys removed pressing the floppy rubber bit down would give a note, but only loud.I peeled the rubber bits back and gently swabbed underneath with an optical cotton bud, and lo and behold it worked fine.The question is, how do these things work? Attached under the floppy rubber bit were two black discs, each about 2.5mm diameter. When the key is pressed these go down and touch two pairs of tracks on the PCB. I am guessing that these are magnets and the tracks are actually Hall sensors? Obviously the tiniest piece of something was keeping the magnets (?) away from the track so not detected.See it all ran on a 64180 with a large custom chip, but not enough pins to give four per key.

author: ataradov
author_rank: Super Contributor
timestamp: May 28, 2019, 08:10:21 pm
content: Tracks are just tracks and the black disks are carbon impregnated rubber, which shorts the contacts on the board. This is a pretty standard design for the buttons.And if the keyboard has velocity sensitivity, then there typically are a pair of such buttons, which are shorted at a slightly different time in the key travel. Time difference between the shorts is proportional to the velocity.Wikipedia article about this type of buttons -https://en.wikipedia.org/wiki/Silicone_rubber_keypad

author: floobydust
author_rank: Super Contributor
timestamp: May 28, 2019, 08:17:53 pm
content: Polyphonic after-touch measures the closed contact resistance, some Roland keyboards had the feature. I did not see it work so well, you have to really press down hard.So some down-key switches were pressure sensitive, not strictly off/on.

author: woodchips
author_rank: Frequent Contributor
timestamp: June 05, 2019, 05:33:31 pm
content: Thanks for the replies.Certainly look like carbon impregnated rubber, couldn't see how the loudness was determined. It is polyphonic and the number of keys and wires didn't allow every key to have four wires. Perhaps it assumes you aren't going to play certain notes together to reduce the number, but then how does it know which note has been pressed?Something so simple in a real piano isn't quite so simple in electronics!The design of the rubber mount prevents any hard pressing down, the rubber simply won't allow it.

author: ataradov
author_rank: Super Contributor
timestamp: June 05, 2019, 06:10:01 pm
content: The keys are probably connected in matrix, and that matrix is actively scanned. See if there is a bunch of diodes on the board.If there are two sets of contacts for each key, then velocity (loudness) is 100% determined by the timing of them shorting out.
Roland MTR 100 / Teac MT-2  pinch roller replacement  - Page 1
Forum section: electronics / repair

author: megatimbo57
author_rank: Newbie
timestamp: March 06, 2024, 09:24:33 pm
content: Hello all does anyone have information about a replacement pinch roller for the Teac MT-2 DAT drive? , and a suitable replacement ,as mine has degraded ,any info i would be grateful for.Thanks M

author: Jeff eelcr
author_rank: Frequent Contributor
timestamp: March 07, 2024, 12:37:48 pm
content: Assuming Teac was a no go, try PRB Projector Recorder Belt company.They may be able to replace the rubber, if possiable, and yes you would have to send it to them.Jeff

author: megatimbo57
author_rank: Newbie
timestamp: March 07, 2024, 10:27:26 pm
content: Hello thanks for the reply ,i will check them outRegards M
Rom writing error - TL866II Plus help - Page 1
Forum section: electronics / repair

author: Pickles
author_rank: Newbie
timestamp: December 17, 2019, 10:24:18 pm
content: Hello everyone,I am in the process of restoring a rom (long story) on a system and I keep getting this error. Not sure what else to do. I had a backup (re-read the chip 5 times and did a checksum with the saved roms). They all seem okay. When i write the image back the rom I get this error (see attached) and not sure what to do...This problem comes up with not only the original rom, the modified rom and even a newly downloaded rom from a known good source...Sorry if I sound really stupid with this, I am kinda new to this whole thing. If there is any other information you need me to provide, let me know. Any help welcomed!Yes, I have tried googling the issue. Absolutely zero results have come back. Maybe wrong search terms? Problem is I don't even know what I don't know....Also, some clarification:Checksum for original image vs itself, no issues. Verified chip prior to writing and compared its contents to the rom saved, no issues.Issue occurs with ANY rom being writen to rom chip.

author: NivagSwerdna
author_rank: Super Contributor
timestamp: December 17, 2019, 11:22:51 pm
content: Post a photo of the device.

author: Pickles
author_rank: Newbie
timestamp: December 17, 2019, 11:41:15 pm
content: Will this do?I just wrote another chip without issues... Is it possible the rom has a bad sector?

author: TK
author_rank: Super Contributor
timestamp: December 18, 2019, 01:38:29 am
content: Is the memory you are programming soldered on the target PCB and powered on?

author: Pickles
author_rank: Newbie
timestamp: December 18, 2019, 03:12:13 pm
content: Honestly wouldn't surprise me. Going to see if I can steal a chip from another system.looks like it was a bad chip! Coolio! Thanks guys!
Roomba discharges battery while on charger - Page 1
Forum section: electronics / repair

author: Carl E
author_rank: Regular Contributor
timestamp: March 10, 2024, 12:39:59 pm
content: Hello,I've got an older roomba. I've installed a new battery. I can charge the battery with an external (Not roomba) charger to 16.3V and the vacuum unit works fine. When I put the roomba on its own charger, the lights appear to indicate it is charging for awhile, however after a couple of hours on the charger, the battery starts yo discharge and after a days is discharges to about 8 volts. The brick charger's output is 22 volts, so it is ok. This happens both with the vacuum on the docking station, or with the brick charger plugged directly into the vacuum. I have tested both the charging station and the battery pack with a different roomba and both work OK. I've also changed out both mosfets ( U2 and U3, P/N N3PF06 ) on the motherboard. I used partial schematics that I found on the web. it's hard to see with the dark background. Anybody had a similar issue or have a suggestion where the problem could be ? ? Thanks !
rosin vapor dispensers for short finding? - Page 1
Forum section: electronics / repair

author: coppercone2
author_rank: Super Contributor
timestamp: February 09, 2022, 02:58:27 am
content: I saw this on youtubehttps://youtube.com/shorts/tn-3ZVfbRhE?feature=shareThat is certainly a interesting idea, to vapor coat the PCB to find shorts.Anyone use this technique? Looks like a poor mans thermal camera.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: February 09, 2022, 03:32:11 am
content: Poor man's Tempilaq, rather.Seems reasonable enough. Only works if the affected spot gets hot enough to melt and coalesce the vapor, of course. Might not work for PCB shorts (low resistance, too much thermal mass?).Any kind of temp-sensitive phenomenon will work, like, you could deposit a fog of... some liquid, and watch where it evaporates more quickly. Like foggy windows, but, water might not be suitable for obvious reasons, alcohol has too low surface tension (forming a film rather than droplets), maybe a slightly heavier alcohol or light oil would do, not sure. Oh, or alcohol with something dissolved in it, possibly rosin again, but another organic compound (or even inorganic salt) that crystallizes well, leaving a white spot as the film evaporates, could show in a similar way. Or a low melting wax, to a similar end as the rosin. Of course you then need to clean off that residue before continuing (unless it happens to be soldering-compatible, like rosin).Tim

author: coppercone2
author_rank: Super Contributor
timestamp: February 09, 2022, 03:52:20 am
content: Hmm, is that safe for electrical circuits though? The rosin things seem you can use for almost anything since everything but very high voltages and precision RF stuff can get away with leaving rosin on the PCB (QC aside).You know you won't be getting anything alien on the PCB if you just use rosin... I actually like working on PCB outside in the cold because you can see broken stuff out gas very visibly... plus it does not smell up the house.

author: all_repair
author_rank: Frequent Contributor
timestamp: February 09, 2022, 05:10:00 am
content: Make desoldering easier also as the joints have flux applied already. Kill 2 birds with one stone.
Rotary encoder replacement in BK Precision 2500 and Agilent DSO3000A scopes - Page 1
Forum section: electronics / repair

author: hanakp
author_rank: Regular Contributor
timestamp: August 10, 2022, 02:25:49 pm
content: I'm posting this because I couldn't Google it directly, so maybe it will help some novice hobbyist. A friend asked me to check out a BK Precision 2530 scope because its front panel knobs didn't work properly. As I soon noticed, theBK Precision 2500 oscilloscopesare based on the same Rigol platform asAgilent DSO3000A series(2005-2010). I know because I (unsuccessfully) attempted to un-brick Agilent DSO3202A a few years back, they use Analog Devices ADSP-BF531 DSP and Altera EP1C6Q240C8N FPGA. Curiously, Rigol apparently never marketed these scopes under their own brand, or at least not with the same front panel layout.Likemany other Rigol instruments, the scope suffered from rotary encoder rot. There are 8 encoders in total, 3 with mechanical detents and switch (larger knobs for volts/div and time/div) the rest without (smaller knobs). All have 24 pulses per rotation; the smaller ones were completely dead, the larger ones were missing pulses. OtherRigol replacement guidesusuallyrecommend metal Bourns PEC11R encoderswith threaded bushing, but the BK Precision scopes use cheaper plastic ones with smooth shaft sleeve. In the end, I used these part numbers:SR Passives EC12E20-24P24C-SW for the 3 detent/switch ones. The detents are slightly stiffer than original, but it felt like improvement. I think Bourns PEC12R-4220F-S0024 would be the closest match among the "respectable" producers.Alps EC12E24104A6 for the 5 ones without detents and switch. I actually tried an encoder with detents first (SR Passives EC12E20-24P24C), but the smaller knobs became uncomfortable to operate. From Bourns, the closest equivalent is probably PEC12R-4020F-N0024.A word of advice - don't attempt to desolder the old encoders the usual way. Their signal leads are a tight fit in the PCB holes and you'll have hard time removing all the solder, even with professional desoldering gun. Instead, snip off the signal leads near the encoder body with fine pliers and only desolder the two thick mounting ones. Then desolder the signal lead stubs one by one and clean the holes.Anyway, here are some keywords so this thread is easier to find:Board marking SAT7.820.269EBK Precision 2530BK Precision 2532B&K Precision 2530B&K Precision 2532Agilent DSO3062AAgilent DSO3102AAgilent DSO3152AAgilent DSO3202A
Rotary incremental encoder for Squeezebox Radio - weird pinout - Page 1
Forum section: electronics / repair

author: Bill Woodbridge
author_rank: Contributor
timestamp: June 01, 2024, 09:21:26 am
content: I’m trying to repair a Squeezebox Radio on which the main rotary knob lost its push-click function, used to select options. Its rotary function remained working, both CW and CCW.I thought I was being very clever sourcing one of those cheap 5-pin rotary incremental encoders as a replacement (Mouser 710-482020514001, Wurth Electronic 482020514001, 20 detent with switch) which apart from cutting down the shaft to the correct height, and making the mechanical case lugs a little thinner to fit the PCB holes, went in perfectly. But on power-up the controls went crazy - rotation (either CW or CCW) seemed to perform the ‘select’ function, and pushing seemed to give random results.It turns out that the standard pinout on the ubiquitous cheap 5-pin encoders like my Mouser replacement (2 pins one side for the push contact, 3 pins other side for the CW, CCW and rotary ground) is not the same as the Squeezebox original part. On the original (no markings on the case whatsoever unfortunately), the push contact is on one of the 3 pins, and CW/CCW are on the 2 pin side (I disassembled it to make sure as I thought I was going crazy). The other pins on the 3-pin side are ground for the push and ground for the rotate, which are connected internally.Before I start mucking about with lifting pins and making a tiny nest of spaghetti pin-pad leads, which I'm not looking forward to at all, does anyone know of a suitable encoder available with this alternative pinout please?Many thanks for any help, Bill

author: mahi
author_rank: Regular Contributor
timestamp: June 01, 2024, 12:39:34 pm
content: Many years ago I used a Panasonic EVE-JBBF2520B (datasheet) to repair a Squeezebox Boom. That has the same pinout as you describe (and it is very likely the Boom and Radio use the same encoder). Sadly, it seems the part is no longer available...

author: Bill Woodbridge
author_rank: Contributor
timestamp: June 01, 2024, 02:13:07 pm
content: Thank you - that Panasonic part definitely looks like the one they used!Unobtanium though it seems, as you say. Looks like the only option is pin-pad spaghetti wiring ....

author: fzabkar
author_rank: Super Contributor
timestamp: June 01, 2024, 07:05:15 pm
content: https://pl.aliexpress.com/item/1005005927768836.html

author: mahi
author_rank: Regular Contributor
timestamp: June 01, 2024, 07:15:25 pm
content: The one and only review of that Aliexpress listing does not look promising:"It's not EVEJBBF2520B. Wrong pin layout."

author: Bill Woodbridge
author_rank: Contributor
timestamp: June 02, 2024, 07:33:58 am
content: It sounds like someone in Poland was as frustrated as me!
Rotek 3960 Calibrator Charred Guessing Game  - Page 1
Forum section: electronics / repair

author: ApertureScience
author_rank: Contributor
timestamp: November 30, 2022, 03:26:09 pm
content: Im currently repairing an old boat anchor Rotek 3960. I replaced a couple bad parts, but two components were charred beyond recognition. The service manual is incomplete or detail got lost in the scanning process.I would guess tantalums, but im not sure. The current output is not only dc, but also ac in the range of 1khz. So adding a bypass capacitor might not be beneficial in the current sense assembly.Thankful for suggestions!

author: ApertureScience
author_rank: Contributor
timestamp: December 11, 2022, 02:17:34 pm
content: I think I should clarify what I replaced in the affected circuit. The zener VR5 was burned. Both VR5 and VR6 are 10V zener diodes. In the current configuration they protect the current output from overvoltage plus or minus 10.5 volt to GND. In the scan one can barely recognize a connection to the output of the power amp (the common input on the CMOS switches IC4, IC5, IC6 at the top).

author: ApertureScience
author_rank: Contributor
timestamp: December 11, 2022, 02:29:54 pm
content: I suspect a capacitor involved somewhere to reduce the CMOS and relay switch noise maybe. There could also be another protection from the output of the amp to GND, to protect the switches and resistors. I attached a functional diagram!

author: ApertureScience
author_rank: Contributor
timestamp: November 27, 2023, 03:53:20 pm
content: Well, it was just two more protection diodes mirrored on the other side. They don't seem to show up in the service manual.

author: ApertureScience
author_rank: Contributor
timestamp: November 27, 2023, 03:55:09 pm
content: Thanks to velik_kazakov for helping me with the service manual and raking some photos of his device
Rotek Calibrator Question - Page 1
Forum section: electronics / repair

author: BiffWheel
author_rank: Newbie
timestamp: January 16, 2021, 07:34:17 pm
content: I have two Rotek Model 610 Wide Band Calibrators. Both power on. I'm having mixed results with both the calibration procedure and getting the units to give consistent results other than the resistance measurements after they are turned off/on again. Does anyone have any insight as to how these units can stay calibrated?Thanks.