hybridfree/eevblog-posts huggingface dataset:
Watch Commander for Sailing - Page 1
Forum section: electronics / repair

author: LagoonCity
author_rank: Newbie
timestamp: October 18, 2024, 03:51:27 pm
content: My friend is a single-handed sailor and has come to rely on an electronic timer that signals him to wake up. It’s relatively simple: set an interval with the rotary dial and, when the time is up, an LED blinks and a soft alarm is activated. If the Reset button is not pressed in a set amount of time, a much louder alarm is activated. Unfortunately, this no longer happens. He sets the alarm and, when the time is up, the LED blinks and the alarm goes off BUT, pressing the Reset button only stops the alarm while pressed. After that, it continues until the rotary dial is set to Test and then back to the desired interval. I’ve attached the original documentation as well as pics of the components at the link below. I’ve worked with Raspberry Pi’s, so have some abilities if the repairs are not too challenging. Otherwise, he’d be ok with sending the unit off for repair if a reasonable price. See pics at:https://share.icloud.com/photos/07dvuixp5K7P2MrFp36JzT-1Q

author: Poroit
author_rank: Frequent Contributor
timestamp: October 19, 2024, 02:49:00 am
content: G'day LagoonCity,Electronics/Electrical gear/wiring on boats often suffer from corrosion problems.Your friends Timer/Alarm would be exposed to some pretty harsh conditions during sailing.Have a close look at the internals, switch and pushbutton for any corrosion.Did the unit have a Silica Gel pack fitted to absorb moisture?

author: LagoonCity
author_rank: Newbie
timestamp: October 19, 2024, 04:19:43 pm
content: Thanks! My first thought as well. Cleaned all contacts with Contact Cleaner and brushed away any obvious corrosion. We are on a freshwater lake, so a slightly less harsh environment.
Watch out for Chinese "AMOLED" replacement screens for Samsung phones. - Page 1
Forum section: electronics / repair

author: Fflint
author_rank: Frequent Contributor
timestamp: March 07, 2024, 08:48:08 am
content: I'm posting this thread here as a warning to others who may want to buy an "AMOLED" screen from China hoping buying "an AMOLED" means it is a refurbished original rather than a locally made inferior replica.Long story short - it is the latter.tl/dr: it has horrible ghosting during movement, it looks good when you display stationary images only.When you tell them you;re unhappy, they ask you for a "video of a problem"Seriously? A video, of ghosting? Well, anyway, to my surprise the ghosting is so bad it does actually show on video...The short version is above. The long version is: As probably many of you I have an older "top tier" Samsung phone with a broken screen that has certain features modern phones do not have (in my case it is gear vr) so I'd like to repair it.I started searching for a replacement screen knowing very well newly made clones are useless, but I though the method to avoid them is to look for words in item descriptions like "LCD, TFT, new" etc, and if the screen claimed to be "original AMOLED" I thought it would be a refurbished screen. The worst I would have to deal with with a refurbished, but working screen is some burn in.So I bought such an AMOLED screen, It arrived, I installed it. The blacks looked great, as an OLED should, but the moment I touched it it felt "strange" (mushy? Original samsung screens feel solid like a piece of glass, this felt like having some give, not as much as the resistive panels of the old, but definitely some). Then I went into the settings menu and I saw what looked like a horrible lag when scrolling (later troubleshooted as ghosting). This makes the screen unusable for fast fps games like NOVA, it makes it look like crap when scrolling any webpage and it makes it totally unusable for the purpose I bought it for - GearVR. If you watch content it is fine, but if you move your head (as you do in GearVR) everything becomes blurry. I even thought this is some software feature until I recorded this screen in slow motion and I noticed an original Samsung screen (albeit on an older S8) refreshes completely differently.Specifically, Samsung's Super AMOLED (on S8 for example - I'll have a refurbished S9 screen to compare with later in the week) switches to dark during refresh. This new screen simply draws the new scene and then it takes time for the old scene to fade. For some time that feels like 10%~15% of the refresh time the old scene remains. This very bad.So, if you just want to make a phone "working", and all you do it watch photos, perhaps putting a screen like this is an option for you(however, if that's all you do, just buy a modern cheap smartphone - you'll have a better battery life). If you browse a lot of scrolled content your eyes will not be happy with this screen, and if you're gaming or using GearVR - forget about it.
Water damage on robotic mower (Worx Landroid WR105SI) - Page 1
Forum section: electronics / repair

author: mdamen
author_rank: Newbie
timestamp: August 06, 2019, 12:51:36 pm
content: Unfortunately my garden got flooded, and thus the robotic mower shorted out due to this.My first target of repair is the motherboard of this thing. Without this it's pretty useless to go ahead with recovery.I was thinking about starting with the power part, and see if that all functions. Would that be a good plan of attack?Is there someone with experience repairing robotic mowers? Or perhaps someone has a service manual of this particular Worx model?I would be very interested in the function of all the test pads.What are the odds of succesfully repairing this thing? It was fully potted with some transparant epoxy so I don't think any water got into the board.So it's more a short damage. The full board does smell quite ugly btw.I attached some pictures. I tried to remove the epoxy as much as possible.

author: m3vuv
author_rank: Super Contributor
timestamp: August 07, 2019, 08:44:35 am
content: i would think the first step would be clean any crud/corrosion from all pcbs and connectors then see what voltages you have going to the board etc.
Wattage rating on this shunt resistor? - Page 1
Forum section: electronics / repair

author: Dave92F1
author_rank: Contributor
timestamp: September 08, 2023, 07:06:22 pm
content: I have a shunt resistor marked "Bader BMN4P/10Q 1R00 V19 0.1".I'm pretty sure it's 1 ohm, 0.1%, but don't know how many watts/amps it'll take.I can't seem to find a datasheet for it. Anybody know the wattage rating on these?It looks exactly like this one (identical package, different markings):https://www.researchgate.net/figure/Shunt-resistance-used-in-the-assays-shunt-resistance-datasheet_fig5_339702401

author: TimFox
author_rank: Super Contributor
timestamp: September 08, 2023, 08:02:20 pm
content: I do not know that particular resistor, but if it were an "ammeter shunt" it would usually be designed for 50 or 100 mV voltage sense, or 100 mA for a 1\$\Omega\$ resistance.

author: fmashockie
author_rank: Frequent Contributor
timestamp: September 08, 2023, 08:03:00 pm
content: I can't find a datasheet for this specific resistor, but given the size and heat sink, I would imagine it is at least a 10W resistor. Always go higher in rating when you are unsure!

author: bdunham7
author_rank: Super Contributor
timestamp: September 08, 2023, 08:20:41 pm
content: The article you linked shows a 10W resistor. Since the part number looks the same except for the nominal resistance, I'd assume yours is 10W as well,likelyalmost certainly requiring a heat sink. You'll need to think about the tempco, the 0R020 one in the article stated 300ppm/C, but your 1R0 might be better.

author: TimFox
author_rank: Super Contributor
timestamp: September 08, 2023, 08:22:44 pm
content: I found the datasheet for the resistor you linked to, which is a smaller resistance.0.02 ohms0.1% tolerance10 W max power< 10 nH inductanceThe authors of the article needed a shunt resistor with small inductance for supercapacitor measurements.

author: fzabkar
author_rank: Super Contributor
timestamp: September 08, 2023, 09:53:22 pm
content: From the research paper ...

author: TizianoHV
author_rank: Regular Contributor
timestamp: September 09, 2023, 08:43:38 am
content: I have some resistors that look the same (series ISA-PLAN, model A-H). Could be some custom order.
Wavetek 154 programmable waveform generator - Page 1
Forum section: electronics / repair

author: trobbins
author_rank: Frequent Contributor
timestamp: May 16, 2020, 01:33:36 pm
content: Just finished repairing and calibrating a Wavetek 154 from the mid 1980's. With 1 millihertz to 10 MHz range, and basic +/-10Vpp square, triangle, sine and +/-10V DC offset functions, and sine distortion down to 0.1% THD for audio range it works well as a basic generator. I haven't yet tried the VCA, VCG or remote control functions.My unit showed heat stress associated with heavy loading (it is rated for 50 ohm loading to 7.5V max AC+DC) of output amplifier - stressed output stage resistors and failed +/- 23V power supply filter caps (the fault). I couldn't fault the other power supply electrolytics for capacitance, leakage or ESR, so they stayed in. The unit comes with its own extender board to assist repair of the plug-in modules. Each of the two plug in power supply modules can be tested on their own with a variac input, to confirm regulation, but all boards need to be in when supplying full mains to avoid heavy loading on some rails.It has analog setting of frequency bands, so no crystal locking like a HP3325.
Wavetek 1701 VHF/UHF Sweep generator Manual needed  - Page 1
Forum section: electronics / repair

author: Marco_Mar
author_rank: Contributor
timestamp: April 05, 2023, 07:12:21 am
content: Hi group.I bought this unit as broken for a few EUR but the manual is unavailable (in free form).It's available on US-Ebay but shipping (I live in Italy) and Customs are scary.Could someone share?Thank you
Wavetek 172b - help needed - Page 1
Forum section: electronics / repair

author: luistrano
author_rank: Newbie
timestamp: February 05, 2023, 04:20:43 pm
content: Hi all.Bought a Wavetek 172b, option GPIB, at low price but high weight...Seemed to work but, altough executing all the command sent via keyboard:- I can have in output only sine waves, at the requested frequency and amplitude, but no way to see a square nor a triangle form, 50ohm or not- the GPIB port is not seen by Keysight sw, seems to be deaf and mute, also if the specific commands via keyboard seems to have effect- 5-8" after executing whatever command the display shows "172b cleared", as if it's resetted, (e.g. the sine output is stopped).So must open the box...but I was unable to find all around the real Service manual: I've found only the User manual.Can someone help for the Service manual? Has anyone an idea of the possible origin of the faults of the instrument?Tnx in advance for your attention and your support.Have all the best,Luigi

author: PA0PBZ
author_rank: Super Contributor
timestamp: February 05, 2023, 04:37:18 pm
content: too big to attach here so:https://drive.google.com/file/d/1YNV5U9E-tVFB-fVTesY8xp1vARxt26P_/view?usp=sharingIt says 'Instruction manual' but it has the schematics and circuit description.

author: luistrano
author_rank: Newbie
timestamp: February 05, 2023, 04:55:27 pm
content: Tnx for the link Paul, I got it yet.Hope to find a true Service manual with detailed schematics, if released.Cuagn, 73 deIK0NKA Luigi

author: PA0PBZ
author_rank: Super Contributor
timestamp: February 05, 2023, 08:39:34 pm
content: Hi Luigi,What are you missing? It looks very detailed to me

author: luistrano
author_rank: Newbie
timestamp: February 06, 2023, 07:10:10 am
content: Tnx once again Paul. Sure I've failed to see at that page...It's enough to start hunting the fox...73sLuigi
Wavetek 178 Repair... complete with shorted component identification. - Page 1
Forum section: electronics / repair

author: TheDefpom
author_rank: Frequent Contributor
timestamp: September 01, 2023, 01:23:56 am
content: I thought I would post some of my recent repairs here, I haven't posted any for a while, this one might interest people.Dead Wavetek 178 Waveform Generator

author: Testtech
author_rank: Regular Contributor
timestamp: September 02, 2023, 11:13:28 pm
content: This is interesting and timely for me. I am currently working on two early version of these monsters for a customer, and they must meet all the specs. I own one like yours, a later version with the 10-turn pots (earlier units had single turn pots that have become erratic) and the dead bug bodge. I was wondering about that, as I don't recall seeing it before. It too had a shorted tantalum, it boots, but no output, a project for another day.I have worked on many of these, there were lots of design tweaks over the years, most undocumented. Getting the older versions to meet spec can be quite time consuming.Thanks for the video!
Wavetek 184 sig gen not making any waveform - Page 1
Forum section: electronics / repair

author: Skyfox
author_rank: Regular Contributor
timestamp: May 15, 2022, 02:49:54 pm
content: I know this is a long shot but I am completely stumped on this issue. I've been working on it off and on for 3 years now, unable to find the fault. I have an old Wavetek 184 signal generator that is not putting out any signal. A few years ago it was working just fine one day, and dead the next. With the schematic and an oscilloscope I can't even figure out where the signal would originate on the board, and I can't find any waveform signal anywhere. The only signals I can find are the sawtooth for the sweep circuit, and the DC offset.The faults I have identified were the two opamps in the power supply circuit that make the ±15V lines. The two lines were about +24 and -5 volts, and replacing the opamps returned those lines to + and - 15V. I also found a bad opamp in the GCV (generator control voltage?) circuit, so replacing that returned a proportional 0-5V on the GCV out BNC when before it was a flat 0V. All of the other voltages test good.The troubleshooting portion of the manual says to try removing one transistor, Q44, to see if the waveform returns, which would indicate a problem in the trigger circuit. Pulling Q44 made no difference, which the manual says would indicate the problem is in the generator loop. I don't entirely know what it means by generator loop. I've pulled and tested every transistor on the main board and power regulator board and they all test good. IC3 is a transistor array (CA3096AE) and all those transistors test good. All the electrolytic caps appear to test fine while in circuit, but I can pull them to test out of circuit if that's advised. IC7 is a SN7400N NAND gate and that tests good (by swapping with a new one that made no difference to the problem). I don't have a real good way of testing the opamps aside from replacement, and a couple of them are the old metal can packages which I don't have.If anybody has any ideas on what else I can check, please let me know, and thanks in advance for any help you can provide. I'd like to fix this thing so I don't have to buy another one but I'm at a total loss and have no idea where I could send it for a professional repair. Here are the pictures of everything, plus the PDF manual which contains the schematics and such.

author: Audiorepair
author_rank: Frequent Contributor
timestamp: May 15, 2022, 03:17:45 pm
content: In the past, I have had problems with vintage synthesisers that use the CAxxx type of transistors array chips.Modern versions of these chips will sometimes just not work, but if you sub in a chip made around the same time the equipment was manufactured, it will.I assume that the original chips had slightly different parameters than those made later, and the synth was designed for the old ones.This happens in oscillator and resonant filter circuits.Kind of bizarre, but I ended up buying two or three hundred pounds worth of original old Harris or Intersil (can't remember) ones from a chip broker to solve my problem. (They all seem to have quite high minimum order values)
Wavetek 186 repair. - Page 1
Forum section: electronics / repair

author: Wojtek44
author_rank: Newbie
timestamp: April 14, 2014, 05:48:05 am
content: Welcome.This is my first post so hello everyone.Sorry for my English but I use a translator.I bought a generator Wavetek 186For sine wave distortion can see the upper and lower halves - the pin.I put pictures.Distortion strongest seen in the range of 100K and 1M.Please help what this can do.Looking for a manual for this generator.If anyone has would really help.

author: Vgkid
author_rank: Super Contributor
timestamp: April 14, 2014, 06:34:39 am
content: Here is one for the 187, specs look similiar. Just scroll down to it.http://ko4bb.com/manuals/index.php?dir=Wavetek

author: Wojtek44
author_rank: Newbie
timestamp: April 14, 2014, 11:34:18 am
content: Generators for which instructions are generally available, are not similar to the model;)As for the distortion sine I do not know where to start looking.It is also possible that such distortions are acceptable in this model.I do not know.So please help more experienced colleagues, who have experience with this model generator.

author: Vgkid
author_rank: Super Contributor
timestamp: April 14, 2014, 04:12:24 pm
content: Below is a parts list, no online manual. You unit has a high ish distortion on the 100k range, and will get worse, basing it on the specs. If the below link doesnt work look up: liberated manuals wavetek 186.http://www.google.com/url?sa=t&source=web&cd=10&ved=0CDkQFjAJ&url=http%3A%2F%2Fwww.liberatedmanuals.com%2FTM-9-6625-2177-34P.pdf&rct=j&q=wavetek%20186manual&ei=HAZMU__CEeaL0QG8tYDwDQ&usg=AFQjCNGiO7d7loK-OA4cAvO_yetyeEkJqA

author: nctnico
author_rank: Super Contributor
timestamp: April 14, 2014, 04:34:52 pm
content: I think you just have to expect these kind of distortions from an RC generator. AFAIK these work by converting a triangle wave into a sine wave so it is logical to have some distortion at the top of a sine wave.

author: Wojtek44
author_rank: Newbie
timestamp: April 14, 2014, 07:36:22 pm
content: Agree. But I also have a generator Interstate F72 to 20MHz. Sine wave is made identically, and the output waveform is clear. In the entire range, there is no spikes.

author: mr_gluc
author_rank: Newbie
timestamp: June 16, 2017, 06:40:57 pm
content: Anyone still interested in finding Service Manual to Wavetek 186?

author: mgonee
author_rank: Newbie
timestamp: April 14, 2025, 12:28:00 pm
content: hi.Here is the schematic for the Wavetek 186.It's very clear. It includes the manual and the schematic together.Good luck.https://elektrotanya.com/wavetek_186_5_mhz_phase_lock_sweep_generator_instruction_manual.pdf/download.html
Wavetek 2001 no 16V signal - Page 1
Forum section: electronics / repair

author: RAPo
author_rank: Super Contributor
timestamp: October 31, 2022, 08:04:10 pm
content: I got a Wavetektek 2001 sweeper.The MH2 module (=sweepdrive) should be generating a 16V signal, but only gives -4.05V.I've measured some critical pins. The green ones (see image) are oke and at pin 10 there is a 32Vpp ramp signal.This module is very tightly screwed to the chassis. Before I try to open it, I have 2 questions:Question 1: Any idea about the source of the error? Moving the pot R95 only marginally changes the signal value.Question 2: in the module is a component TD101, a six-legged NPN-NPN matched transistor pair. Any idea how to test this component?Thanks in advance for the help.
wavetek 23xt slow voltage rising on dc range - Page 1
Forum section: electronics / repair

author: ivi_yak
author_rank: Regular Contributor
timestamp: April 29, 2020, 11:50:19 pm
content: Hi,I have a problem with Wavetek 23xt,when I measure voltage on DC range its start slowly rising to voltage in circuit also when I short probes its start slowly discharge to zero from voltage I have get.Could anyone have the same one bug what it could be?

author: dacman
author_rank: Frequent Contributor
timestamp: April 30, 2020, 09:50:23 pm
content: Clean the function switch contacts and use a contact lubricant.

author: ivi_yak
author_rank: Regular Contributor
timestamp: April 30, 2020, 10:00:23 pm
content: Do you mean function selector wheel? thx for reply

author: dacman
author_rank: Frequent Contributor
timestamp: May 01, 2020, 11:02:12 pm
content: Yes. Clean the contacts that are controlled by the knob used to select the different functions and ranges.

author: jackthomson43
author_rank: Contributor
timestamp: May 02, 2020, 07:16:47 am
content: You should clean your electronic devices regularly. I think you should open it up and do a little dusting.https://www.theengineeringprojects.com/2019/09/schottky-diode-schottky-barrier-working-application-characteristics.html

author: ivi_yak
author_rank: Regular Contributor
timestamp: May 10, 2020, 03:10:51 pm
content: Fixed!I found two sprinned balls which maintain switch-wheel have lost their positions and the contact pressure was not enough to hold functionality.Reinstall them with vaseline and back to lifethanks all for reply
Wavetek 2407 - Page 1
Forum section: electronics / repair

author: ee1993
author_rank: Newbie
timestamp: June 02, 2022, 03:47:13 pm
content: Boat anchor test instrument question: I have a Wavetek 2407R with failing RF. It’s a 500 MHz signal Generator with FM Deviation meter. Trying to decide if it’s worth repair or maybe try the repair as a learning exercise. The “R” designation, I believe, stands for Ruggedized as this unit is in a molded case with cover and internal surround padding. Likely intended for field maintenance of repeaters, as the instrument includes an FM deviation meter.It has set unused for many years now. The instrument passes its internal self-checks and will output a clean signal at first, but soon begins jumping around the set frequency and eventually settles down but extremely noisy. If left on long enough, it will lose lock and output a clean signal way off frequency. I suspect power supply issues but have yet to open the unit. I do have a manual (typewritten for 1988 or so).Anyone here have any experience with this Signal Generator?

author: TimFox
author_rank: Super Contributor
timestamp: June 02, 2022, 04:44:31 pm
content: I own a non-R Wavetek 2407. A manual for it is available athttps://bama.edebris.com/download/wavetek/2407/Wavetek_2407_Operating_with_Service.pdf(Maybe the same "typewritten" manual you have.)Mine was received in operating condition, but was out of calibration. If you are able to restore its function, you will need a device to measure its output over the frequency range in order to get the power output calibration table updated.I haven't used the deviation meter, but mine works well as an FM or CW generator.

author: ee1993
author_rank: Newbie
timestamp: June 02, 2022, 05:26:15 pm
content: Thanks. I found this:http://www.radiomuseum.co.uk/wavetek.htmlAfter reading through, it seems that my problem is likely the same as his was. I was testing at 100MHz and he found that the problem went away for all frequencies above 137.5 MHz. The lower frequencies are mixed down through a different path. I then verified that my unit has clean signals at 200MHz. Well, relatively clean as it has upper and lower spurs 70 dB down 450KHz above and below the main. Calibration seems to be close as measured on my old HP spec an. I'll plan to open the beast and take a look at the RF card.
Wavetek 27XT not working - Page 1
Forum section: electronics / repair

author: status1
author_rank: Contributor
timestamp: September 05, 2019, 11:34:11 pm
content: Hello,I am looking for some help in troubleshooting a Wavetek 27XT that no longer worksThe history on this is that I used this for many years at work and one day it stopped workingso rather than throwing it out I took it home in case I could fix itI read some of the posts here and other websites but it did not help with the problem this meter is havingBasically the problem is that it's not measuring anythingI can touch the leads together and there is no change on the display so on the resistance scale touching the leads together would read openI took it apart but I did not see any obvious damageI used another meter to check continuity of the leads up to the back of the pcb so the leads are good and connected to the boardI know it's very difficult to repair something without a schematicIs there any place in particular I should start looking ?Any help would be appreciated

author: floobydust
author_rank: Super Contributor
timestamp: September 06, 2019, 12:12:02 am
content: Schematic atElectrotanyaWhat does it do on DCV on a battery, does it read around 1.5V?

author: status1
author_rank: Contributor
timestamp: September 06, 2019, 03:13:35 pm
content: Thanks for the replyThat schematic is for the 27XL while I have the 27XTI am not sure what you are askingI cannot measure anything with this meterDo you mean to measure something with another meter ?

author: ledtester
author_rank: Super Contributor
timestamp: September 06, 2019, 06:17:33 pm
content: You might find this post in the Antique Radio forum helpful:https://www.antiqueradios.com/forums/viewtopic.php?f=8&t=166996&start=20The guy had a similar problem - "... the meter still did not work - it always read the same value independent of the range or function."

author: floobydust
author_rank: Super Contributor
timestamp: September 06, 2019, 07:17:28 pm
content: OP has already cross-posted there, more responses:https://www.antiqueradios.com/forums/viewtopic.php?f=8&t=364270

author: status1
author_rank: Contributor
timestamp: September 06, 2019, 10:33:07 pm
content: Quote from: floobydust on September 06, 2019, 07:17:28 pmYes I read that post but I did not think it would help me because my meter does not have the same problem The problem is not that it's reading the same value The problem is that it does not read any value on any rangeYes I posted over there because I saw that post first and I thought perhaps someone may have gathered more knowledge since thenThan later on I saw some posts over here so I thought I could post over here as well to diversify the responses I meant no offense to anyone
Wavetek 5XL no capacitance measurement - Page 1
Forum section: electronics / repair

author: Axtman
author_rank: Regular Contributor
timestamp: November 16, 2019, 10:27:21 pm
content: I recently bought a used Wavetek 5XL multimeter. I know that it is a cheap, manual-ranging, averaging multimeter and probably not worth fixing. That said, I like it and would like to try and repair it.The multimeter measures VAC, VDC, resistance, continuity, and diodes correctly. It does not measure capacitance at all. Every range just shows 0.00. Any ideas where I should start troubleshooting? Thanks.

author: lowimpedance
author_rank: Super Contributor
timestamp: November 17, 2019, 12:26:19 am
content: Perhaps some photos of the PCB might help . Hopefully its using a known chip set and you could find more hints that way.

author: retiredcaps
author_rank: Super Contributor
timestamp: November 17, 2019, 01:34:06 am
content: Assuming this is the same meter, where do you see capacitance?I see, clockwise, ACV, Amps, diode/continuity, ohms, and DCV.

author: retiredcaps
author_rank: Super Contributor
timestamp: November 17, 2019, 01:35:19 am
content: If you mean Amps not working, check for blown fuse.

author: retiredcaps
author_rank: Super Contributor
timestamp: November 17, 2019, 01:45:09 am
content: Manual shows no capacitance mode in 5XL. Only 16XL.https://assets.tequipment.net/assets/1/26/Documents/5XL10XL15XL16XL_Manual_Rev_A.pdf

author: Axtman
author_rank: Regular Contributor
timestamp: November 18, 2019, 05:54:35 pm
content: "An the winner of the 2019 EEVBLOG Idiot Award goes to........" (drum roll) (opening envelope) "me"Hey! You fixed it! Thanks! Now can you work on my eyes and/or brain?!Boy do I feel like a complete dope. I'm glad that this forum lets people post regardless of the mental capacity. I'm really not that stupid in real life.I'm not sure why I thought the amps range was capacitance. I guess I should have been more shocked if I actually got a reading.Thanks Retiredcaps. At least YOU were paying attention.
WAVETEK 9100 Service Manual. the search of the missing schematics.  - Page 1
Forum section: electronics / repair

author: Martin Miranda
author_rank: Regular Contributor
timestamp: January 05, 2022, 05:01:43 pm
content: WAVETEK 9100 Calibration Systemis there anyone who can scan or has a copy for this calibrator?

author: Martin Miranda
author_rank: Regular Contributor
timestamp: January 08, 2022, 04:14:35 pm
content: UP. just in case there is a soul out there that has the schematics / service manual.

author: alm
author_rank: Super Contributor
timestamp: January 08, 2022, 04:41:20 pm
content: I don't have anything, but forum memberKenhas been collecting Wavetek 9100 documentation for a while. I'd send him a PM to ask if he has any leads.

author: Martin Miranda
author_rank: Regular Contributor
timestamp: January 08, 2022, 04:53:43 pm
content: Quote from: alm on January 08, 2022, 04:41:20 pmthanks i sent a pm. thanks!

author: picburner
author_rank: Frequent Contributor
timestamp: January 08, 2022, 06:44:14 pm
content: You can find the wavetek 9100 schematics and the service manual on theko4bbwebsite.

author: Martin Miranda
author_rank: Regular Contributor
timestamp: January 08, 2022, 07:00:24 pm
content: if you planned to have a vacation here in manila, i'll treat you around!thank you very much!i searched ko4bb but i never searched it THAT THAT deep.

author: Testtech
author_rank: Regular Contributor
timestamp: January 10, 2022, 11:29:39 pm
content: What is wrong with it?

author: Martin Miranda
author_rank: Regular Contributor
timestamp: January 11, 2022, 03:44:36 am
content: https://www.eevblog.com/forum/repair/im-now-a-happy-owner-of-a-boat-anchor-wavetek-9100-calibrator/msg3927785/#msg3927785

author: coromonadalix
author_rank: Super Contributor
timestamp: January 11, 2022, 08:33:46 am
content: Would be nice to not double post for the same equipement .......

author: Martin Miranda
author_rank: Regular Contributor
timestamp: January 11, 2022, 08:37:37 am
content: Quote from: coromonadalix on January 11, 2022, 08:33:46 amsorry bout that. i'm still new to the forum.this thread can be deleted. but i don't know how.
WaveTek DM27 meter issue - Page 1
Forum section: electronics / repair

author: Serracin
author_rank: Newbie
timestamp: October 16, 2018, 02:51:37 pm
content: This meter is showing erratic measurements.If I remember right, there is a chip that needs to be changedAny ideas please?

author: coromonadalix
author_rank: Super Contributor
timestamp: October 16, 2018, 09:37:18 pm
content: service manual :https://elektrotanya.com/wavetek_dm-23xt_25xt_27xt_info_sch.pdf/download.htmlorhttp://www.xn--80alh0b.xn--p1ai/DOWNLOAD/dm27.pdfThe main chip is an icl 7106 and doesn't cost a fortune, Datasheet :https://www.intersil.com/content/dam/Intersil/documents/icl7/icl7106-07-07s.pdfYou have a couple of TLO62 op amps, and u70 is an 3ra024 ic, i think its an proprietary icseen old un-answered threads for searching this same ic

author: lowimpedance
author_rank: Super Contributor
timestamp: October 16, 2018, 11:26:29 pm
content: Quote from: Serracin on October 16, 2018, 02:51:37 pmJust a thought if its kind of functioning, perhaps averygood clean is a simple enough exercise. From the outer casing, input terminals to the PCB itself.Check for any bad/cracked joints etc. and the switch selector traces are in good condition first before thoughts of chip replacement.Contamination around the ADC of the 7106 will manifest as unstable drifting measurements.Note, without pictures I have no idea how clean or otherwise your unit is!.If cleaning does not help then a good think as to whether this meter is worth further effort or its time to treat yourself to a new DMM. depending on how many you already own of course.

author: EzeMelano
author_rank: Newbie
timestamp: May 23, 2023, 12:36:29 pm
content: Can you repair this Multimeter? I have the same model Wavetek DM27XT and the AC scale display -13V when i dont testing anything. Whe i test an AC voltage the measure display the real signal - 13V.In all other function it is OK.
Wavetek Meterman 235 - Page 1
Forum section: electronics / repair

author: goaty
author_rank: Regular Contributor
timestamp: November 18, 2021, 10:26:23 am
content: Got a Wavetek Meterman 235 Multimeter "T-Shaped",which only is 'on' on the 'OFF' position and 'off' on all other positions.When on, does not do anything sensible but displays some current range and random values.Anyone got some schematic / tipps / hints on that device ?Thanks, Thomas

author: Doctorandus_P
author_rank: Super Contributor
timestamp: November 20, 2021, 12:24:20 am
content: I've got a Meterman 35XP.Start by opening the thing and getting a datasheet from the main measurement IC.Most functions of a DMM are implemented in a single chip, and that chip dictates most of the internals.It's probably not very difficult to match an example from the datasheet to your meter.
wavetek phase meter model 740 schematic or manual wanted - Page 1
Forum section: electronics / repair

author: oz2cpu
author_rank: Frequent Contributor
timestamp: January 03, 2023, 08:48:36 am
content: i got a rather cool wavetek phase meter model 740it is FULL of trimmers, it needs a little bit of adjustments,i feel someone before me, tried to trim a bit here and there, while seeking the right pots,so i could really need a service manual or schematic, so it can be done correctlyhere you can see the state of my instrumenthttps://youtu.be/F1rcYVERanQ
Wavetek/Datron 9100 Multifunction Calibrator Unable to boot - Page 1
Forum section: electronics / repair

author: CrazyTiger
author_rank: Regular Contributor
timestamp: April 29, 2022, 12:00:09 am
content: Hi,I found myself a Wavetek 9100 today, it cannot boot. Upon powerup the instrument turns on with a blank white display and stays there. I managed to find the service manual and schematic onhttps://ko4bb.com/.So far i have confirmed that PSU voltages are correct. So now I am having a look at the digital processor board. Will be probing the SRAM for activity later today. I also saw its using a Dallas 1287 RTC.Is there be a possibility a dead battery in it cause the unit to not turn on?. Any wavetek 9100 user out there that can advice me on this?

author: ebclr
author_rank: Super Contributor
timestamp: April 29, 2022, 02:25:00 am
content: Where did you find service manual, on the link only operational manual, I would love to have the real service manual

author: CrazyTiger
author_rank: Regular Contributor
timestamp: April 29, 2022, 03:11:19 am
content: Well, I wont say its a conventional service manual, not sure how to name it, but here is the link:http://www.ko4bb.com/getsimple/index.php?id=manuals&dir=06_Misc_Test_Equipment/Datron/Datron_9100Progress Update:I have already unsoldered the Dallas chip and drill a hole to probe for the battery voltage, its dead.Will solder an external battery shortly to see if it does something.

author: Testtech
author_rank: Regular Contributor
timestamp: April 30, 2022, 09:06:43 pm
content: Part of the SM is here :http://www.bitsavers.org/test_equipment/fluke/9100/9100_svc_part1.pdf

author: CrazyTiger
author_rank: Regular Contributor
timestamp: May 01, 2022, 10:55:06 am
content: This manual is for 9100A, a Digital Tester. Maybe fluke got stuck with Datron's model number when they rebadged and ended up getting stuck with 2 different instrument with similar model number?Anyway, it was not the Dallas RTC, it was a long shot to begin with. Will continue my diagnose

author: jsolomonsc@gmail.com
author_rank: Contributor
timestamp: September 22, 2022, 12:24:16 am
content: Make sure that the dip switches 6, 7 and 8 in the back are set properly.
Wayne Kerr 6245 Help - Option Board Photograph Request - Page 1
Forum section: electronics / repair

author: brim2full
author_rank: Newbie
timestamp: December 09, 2020, 10:22:43 am
content: I recently acquired a faulty 6245 which was apparently unrepairable. However it turned out to be a hand-fisted techie splashing solder in the unit.My unit does not have any of the internal options, specifically the GPIB option. I have the service manual and I am in the throws of re-making the board. The manual does have the component placement and that will help. However I know service manuals are not always up to date and do contain errors. Therefore if any one cares to post a few high-res photos of the option boards, specifically the GPIB option. I will bless you at Christmas.Many thanks and keep safe.

author: EHT
author_rank: Frequent Contributor
timestamp: December 09, 2020, 07:30:03 pm
content: That name must have provided a lot of laughs over the years, esp as its Britishhttp://www.waynekerrtest.com/history.php.
Wayne Kerr B605 PROM's required please - Page 1
Forum section: electronics / repair

author: Leighcrx
author_rank: Newbie
timestamp: August 03, 2019, 04:27:08 pm
content: Hello Forum,Wondering if any of you lovely people have a copy of the PROM files for the Wayne Kerr B605 automatic component bridge.I have 2 units (1 is in kit form, does not have a case), comparing the contents of the EPROMS seems very random so suspect they have suffered partial erasure etc, well the have been kicking about since the 80'sHave searched loads of the download sites, but nothingI need PROM 1 (IC129) and PROM 2 (IC30) programs to hopefully make at least 1 unit come alive.I don't care what format the data is in!Thank you in advance, kind people.

author: Andy Watson
author_rank: Super Contributor
timestamp: August 03, 2019, 04:38:43 pm
content: Which version ? I have a dump of the ROMs from the early, S/N < 375, meter. This is the four-ROM set. The later versions used two ROMs but I believe the remaining hardware was essentially the same - so they might work.

author: Leighcrx
author_rank: Newbie
timestamp: August 05, 2019, 06:56:40 pm
content: Thank you Andy Watson,mine is the 2 ROM version (serial number 415).Any how I will try out the 4 ROM version and see what happens.May be a while before an outcome as have a couple of other projects on the go.Thanks again.
Weak eye pattern = weak laser? - Page 1
Forum section: electronics / repair

author: Circlotron
author_rank: Super Contributor
timestamp: May 28, 2019, 05:40:15 am
content: Having a look at a friend's 20 yo Pioneer CD/cassette/tuner thing. Tray wouldn't eject - busted belt. Then a CD woudn't start spinning - dusty laser lens means it couldn't focus on the disc so couldn't detect it's presence. Then it would only play some discs and not others, all originals, none were CDRs. Looked at the eye pattern and the manual says it should be about 800mV p/p but I could only see 400mV p/p. Twiddled the pot that affects the symmetry of the eye pattern (at work right now, can't remember the name) and it was already optimum. Increased the laser brightness just a little and the eye pattern amplitude increased about 5% and it would now play all the discs but still skipped every 20 or 30 seconds. If I wound the brightness up more than a little the eye pattern would go off to one side and the thing would quit playing. Should I increase it slightly and then adjust the symmetry control to get it right, then up the laser a little more etc? Not to far of course - I read that they can conk out quite easily. Or is the laser just worn out and there is not much that can be done other than replace it? I also oiled the sled rail.

author: shakalnokturn
author_rank: Super Contributor
timestamp: May 28, 2019, 07:49:17 am
content: A weak eye pattern often is due to a weak laser, there are a few points to check before replacing the pickup or cranking the laser power up to get the last hours out of it.As usual make sure power is clean first.Play jumping at a fairly long regular interval as in your case could be due to dirt on the sled motor reduction gears.If there was plenty of dirt on the lens make sure you cleaned it well enough, it would also be worth blowing under the lens (holding it to not tear it off it's hinges) with a can of dry air. Fine dust will also deposit on the prism under the lens.It may be worth checking the power decoupling and solders on the focus/tracking coil drivers.When I repair a (vintage) CD player I'll usually also check the spindle and sled Mabuchi motors using an oscilloscope with "component tester" function and 10X horizontal magnitude. Spinning the motor by hand will show the electric state of the motor, dirty brushes are usually fixed with contact spray.I'll also try to check that the disc support has not moved down on the spindle motor axle. Sometimes this will stop the player from playing at all, other times it will play some disks and skip often, the focus servo will have a hard time. Only fiddle with this if you're really sure it has moved.After that I'll try to get a disc to play, scope the eye pattern (If referring to an amplitude on the service manual make sure your scope/probe BW is sufficient) adjust the focus for highest amplitude, adjust the tracking for a compromise of highest amplitude without it being too noisy (acoustic noise).Check with a CD-R.Only after all this I'll consider playing with the laser power.
Weird (??) display in Tek 2465BCT CAL01 procedure - Page 1
Forum section: electronics / repair

author: rodd
author_rank: Regular Contributor
timestamp: December 02, 2020, 11:15:01 am
content: Dear All,After fixing the A5 board of the scope which was damaged due to capacitor leakage I have started to try to calibrate the scope.I managed to adjust DAC REF without any issues and moved to CAL01.After trying to read as much as I could about the automated cal steps, I managed to find a very good post from Randy Peckenpaugh, wb0smx at his website which documented all the calibration steps of a 2465A WITH PHOTOS!See (http://www.wb0smx.net/?cat=62&paged=3).I am using a TG501 with a 50 ohm termination (just to make sure I do not overload the scope input) as the "signal source" with a coax Tee attached to the output.One side of the tee is connected to the 2465 using a TEK 012-0482-00 precision coax cable and the other side is connected to my TDS2024B that is used to "monitor" the signal used for calibration.The 50 ohm termination and the signal monitoring scope are just precautions since the TG501 is rarely used and it may go crazy during the calibration procedure.I could follow the procedure without problems until I reached step n.The 2465BCT display is very different from the pictures, and the display is not "stable" as it was on the previous steps.Also, I could not obtain a well defined pulse at the Delayed B sweep trace as I could see in the picture of the above-mentioned reference.What I see one near horizontal line and one curved that shift when I move the DELTA knob.I have started a new picture album with a movie and some photos of what I am getting as well as the behaviour shown in the reference.Any help will be welcome.Roger

author: TD
author_rank: Contributor
timestamp: February 08, 2021, 03:04:43 pm
content: You can access(http://www.wb0smx.net/I have not been able to access Randy's wb0smx site?I just learned about Randy's site a couple weeks ago.However, every time I try to access the site it gives an error that the site is hot responding. Error is This page isn’t workingwww.wb0smx.net didn’t send any data.ERR_EMPTY_RESPONSE.I can't find any other info. so when I noticed you posted a link within the past month I thought I would ask so I could find out if it's just me or not. Maybe I am having an IP address issue or something.thanks
Weird issue with laptop screen  - Page 1
Forum section: electronics / repair

author: Srivatsa R Upadhya
author_rank: Newbie
timestamp: September 20, 2022, 06:00:30 pm
content: Hi, I have a ThinkPad L420 that I have been using for a very long time (More than 9 years now). It still works fine but the screen gave up with a strange fault. I don't know how to describe it, it is kinda lagging and dragging contents. when things on the display changes the previously displayed content stays for a while and slowly fades away. There is no problem with an external monitor it's just with the laptop screen. I have tried reinstalling the drivers and it gave me an error message saying, "Windows has stopped this device because it has reported problems (Code 43)". I also tried reseating the RAM sticks and the processor, but it didn't change anything.It is very old and there is no point in using it anymore but I'm just curious to know what the problem might be!Here is a video of the screen:https://1drv.ms/u/s!Atxh0g8rKAR_jSrj6m4Mcf4D2Okd?e=qZrcKJ

author: unknownsoldier90
author_rank: Contributor
timestamp: September 21, 2022, 06:49:48 pm
content: LCD panel or display cable. Often it’s the LCD Panel itself
Weird oscillator issues in robot vacuum cleaner (Samsung SR8845, PIC32MX) - Page 1
Forum section: electronics / repair

author: nathanel23
author_rank: Newbie
timestamp: January 09, 2022, 11:21:45 pm
content: I got a SR8845 vacuum cleaning robot which doesn't turn on any more. Previous owner suggested that it's just the batteries and those were in deed totally discharged. However, even with a new battery pack installed the robot still was completely dead.So I disassembled the unit and took out the main board and attached to bench power supply and started probing around with the oscilloscope. Logic rails 3.3V and 5V are generated all fine from the battery voltage.As I touched a pin of the 8 Mhz ceramic resonator with the oscilloscope probe, the board suddenly came back to life. First I thought like maybe it's some cold solder joint, but putting some fresh solder didn't make any difference. At this point it looked like the issue is fixed by the additional load capacitance from the probe, which obviously brings the oscillator circuit back into working condition.Gluing the oscilloscope probe onto the board permanently is not an option, so I figured that maybe just the ceramic resonator was already marginal from the factory and I proceeded by ordering some replacement that looked reasonable. The PIC32MX user manual mentions typically something in the area of 22pF to 33pF load capacitance is needed, and the replacement ceramic resonator I selected was listed as 30pF in the datasheet. As you may already guess, this unfortunately didn't work out as expected.Currently I'm experimenting with building a replacement circuit for the ceramic resonator built from a regular 8 MHz quartz and two separate ceramic capacitors. This should give better control over the capacitance. I only tried few variants, but the only way I got it working again so far was with 18pF caps while touching again with the oscilloscope probe. With the probe removed, the PIC32MX microcontroller ceased working again within a few seconds.Attached picture of the location of resonator relative to microcontroller, as well as bottom side of the board where original ceramic resonator was installed.Is this normal that the oscillator circuit for these microcontrollers is so sensitive regarding proper load capacitance? Maybe something else is actually broken and the oscilloscope probe is doing something else that I'm currently overlooking?