Simpson 262 series 3 repair  - Page 1
Forum section: electronics / repair

author: bsalai
author_rank: Regular Contributor
timestamp: December 18, 2016, 04:32:43 pm
content: I'm trying to repair an old Simpson 262 series 3.It works on some ranges but is out of calibration. There are four calibration potsbut no labels on them to identify which is which.Also, there are at least two resistors that are burned up on the top middle portion of the boardThe values are unreadable and I can't find a schematic.Does anyone have any experience with this meter or a source for a schematic or at least the parts layout.Thanks,Brad W2EKSent from my iPhone using Tapatalk

author: ModemHead
author_rank: Frequent Contributor
timestamp: December 18, 2016, 05:32:44 pm
content: The operator's manual contains a schematic and is available at simpson260.com.http://www.simpson260.com/downloads/simpson_262-3_user_manual.pdf

author: Fisher77
author_rank: Regular Contributor
timestamp: December 18, 2016, 07:37:37 pm
content: Here is the schematic and parts list for your meter.

author: bsalai
author_rank: Regular Contributor
timestamp: December 18, 2016, 11:05:40 pm
content: Thanks very much. Do you also have a drawing showing parts layout?I may actually be able to fix this thing! I really appreciate your help.BradSent from my iPhone using Tapatalk

author: Fisher77
author_rank: Regular Contributor
timestamp: December 18, 2016, 11:15:15 pm
content: No unfortunately I don't. I scoured the net looking for one, and could not find one.Can you remove the board, and post a picture of the bottom side?

author: bsalai
author_rank: Regular Contributor
timestamp: December 18, 2016, 11:22:19 pm
content: Here you go.The bad resistors are the two to the left of the middle battery post, between the post and what looks like a resistor formed from wire wound around a bobbin.Sent from my iPhone using Tapatalk

author: bsalai
author_rank: Regular Contributor
timestamp: December 18, 2016, 11:26:07 pm
content: I just noticed that the picture is upside down, the two bad resistors are to the right of the battery post in this viewSent from my iPhone using Tapatalk

author: bsalai
author_rank: Regular Contributor
timestamp: December 19, 2016, 12:17:15 am
content: Quote from: bsalai on December 18, 2016, 11:26:07 pmSent from my iPhone using Tapatalk

author: bsalai
author_rank: Regular Contributor
timestamp: December 19, 2016, 12:21:16 am
content: Following the schematic and tracing the board, I'm pretty sure the blown resistors are R5 and R6. They are not standard values. 1478 and 4242 ohms. Does anyone know if there is a source for these?Sent from my iPhone using Tapatalk

author: Fisher77
author_rank: Regular Contributor
timestamp: December 19, 2016, 02:32:09 am
content: Something is off here.The meter face says 262 series 3, but the circuit board says 269-2.Is it possible this is a 269-2 that had the meter movement replaced with a 262-3 meter movement?

author: bsalai
author_rank: Regular Contributor
timestamp: December 19, 2016, 09:04:59 am
content: It is certainly possible. There are signs of an earlier repair. I noticed that one of the other resistors in the current section had been replaced by cutting out the old one and soldering a new one to the old wires. Also, the solder connections to the meter terminals had a lot of solder on them. They were solid, but didn't look professionally done.BradSent from my iPhone using Tapatalk

author: Gyro
author_rank: Super Contributor
timestamp: December 19, 2016, 10:12:51 am
content: Quote from: bsalai on December 19, 2016, 12:21:16 amThe simplest way is to use a series or parallel combination of standard resistor values. With a bit of calculation, you can get very close that way.

author: Fisher77
author_rank: Regular Contributor
timestamp: December 19, 2016, 01:48:35 pm
content: I found a guy that has one. He is going to try to crack it open to today and take some pics of the inside. He has to locate it first, he does alot of exhibits at shows and fairs, so it is packed away in a box. I will post back when I hear back from him. Beleive it or not the recommended way to replace resistors in the manual for my 260 series 3 is to cut the old one out, and solder the new one to the old leads. So that is a definate sign of a previous repair.

author: bsalai
author_rank: Regular Contributor
timestamp: December 19, 2016, 07:49:03 pm
content: Quote from: Fisher77 on December 19, 2016, 01:48:35 pmSent from my iPhone using Tapatalk

author: bsalai
author_rank: Regular Contributor
timestamp: December 19, 2016, 07:50:31 pm
content: That would eliminate the need to remove the board, which isn't difficult but does require unsoldering four wires attached to the meter.Sent from my iPhone using Tapatalk

author: bsalai
author_rank: Regular Contributor
timestamp: December 19, 2016, 07:53:18 pm
content: Interesting thing is, the component values on the board match the 262-3 schematic and parts list you sent. Maybe the 292 is the same though.Sent from my iPhone using Tapatalk

author: bsalai
author_rank: Regular Contributor
timestamp: December 19, 2016, 07:55:04 pm
content: Oops, I meant 269.Sent from my iPhone using Tapatalk

author: Fisher77
author_rank: Regular Contributor
timestamp: December 19, 2016, 10:43:02 pm
content: Ok, I heard back from him. The resistor values in his, match yours exactly. I guess they just decided to use the 269-2 board in both meters. You are correct on the resistor values. I have looked at Digikey, Mouser, and Newark. None of them have the 1.478k, or the 4.242k. You may have to just get as close as you can say like 1.47k, and 4.27k or series some together to get closer the values. I had to do that in my Simpson 260 series 3. I couldnt get he exact values for the bobbin resistors, so I had to series 2 wirewound resistors to get as close as I could. I will look at a couple of other places and see what I come up with.

author: bsalai
author_rank: Regular Contributor
timestamp: December 20, 2016, 10:04:37 pm
content: I looked at did you key and didn't find anything close, but I may not have looked at exactly the right place. Do you remember where you found or think I might find 1.47 or 4.27k?Sent from my iPhone using Tapatalk

author: dacman
author_rank: Frequent Contributor
timestamp: December 20, 2016, 11:09:52 pm
content: Digikey shows 1.476k, 1.48k, 4.23k, and 4.25k, although none are in stock and the minimum buy is 1000 or more for each.PRC (Precision Resistor Company) in Florida could make the exact values (with tolerances as low as +/- 0.005%), although the price would be maybe $75.00 each value but you would get a handful of both values. They make wire-wound resistors but the HR series is wound to cancel inductance.

author: Fisher77
author_rank: Regular Contributor
timestamp: December 21, 2016, 12:05:53 am
content: Here are some from Mouser. First link is a 4.3k, the second link is a 1.47k. That is the closest ones I could find. Both are in stock with a mimimum of 1 to order.http://www.mouser.com/ProductDetail/Yageo/MFR50SFTE52-4K3/?qs=UFD7vfw3J8pZ6CEWkRTgIg%3d%3dhttp://www.mouser.com/ProductDetail/Vishay-Dale/RN70C1471FB14/?qs=sGAEpiMZZMu61qfTUdNhGy2XqlsoYCVGliDjF9bdsJU%3d

author: BFX
author_rank: Frequent Contributor
timestamp: December 21, 2016, 12:10:25 am
content: Or buy 20pcs or more of those values and pick the closest one.

author: tpowell1830
author_rank: Frequent Contributor
timestamp: December 21, 2016, 12:13:20 am
content: Quote from: Fisher77 on December 19, 2016, 02:32:09 amMaybe reach out to Dave, he recieved a 292 in Mailbag special @ 3:57:PEACE==>T

author: Fisher77
author_rank: Regular Contributor
timestamp: December 21, 2016, 12:17:51 am
content: Quote from: tpowell1830 on December 21, 2016, 12:13:20 amFound a guy on youtube that had a 262-3. He cracked it open and emailed me pics of the inside. bsalai's meter matched it.

author: tpowell1830
author_rank: Frequent Contributor
timestamp: December 21, 2016, 12:29:13 am
content: Quote from: Fisher77 on December 21, 2016, 12:17:51 amHey, even better. Maybe post pics or at least a link to all so others can benefit?I have a Simpson Model 260. I love the old vintage Simpsons.PEACE===>T

author: Fisher77
author_rank: Regular Contributor
timestamp: December 21, 2016, 06:29:31 am
content: Quote from: tpowell1830 on December 21, 2016, 12:29:13 amI picked up a 260 series 3 at a garage sale for $5. It had prolly been in the persons attic for 20 years. Batteries had leaked all over the place. I sought help right here on how to fix it. Took alot of cleaning, and had to reflow the solder joints, but it works now, and I like it. Everything measures in spec of the meter except the DCV. I am going to have to look into the problem.Here are the pics of the 262-3 courtesy of AllAmericanFiveRadio on youtube:

author: bsalai
author_rank: Regular Contributor
timestamp: December 21, 2016, 10:43:58 am
content: The specs for the meter are only a few percent so I'm thinking that I can get close enough with just a couple of values from Digi-Key. Only problem is the minimum order. I don't suppose there are 900 or so people reading this who would like to go in on an order with me?Is there a source for smaller numbers? I'd be willing to pay a few $ for one or two, but the meter is probably only worth $50 in good shape, and the sentimental value to me is $3.74, more or less!Sent from my iPhone using Tapatalk

author: BFX
author_rank: Frequent Contributor
timestamp: December 21, 2016, 12:35:06 pm
content: Quote from: bsalai on December 21, 2016, 10:43:58 amDid you try farnell?http://uk.farnell.com/

author: Fisher77
author_rank: Regular Contributor
timestamp: December 21, 2016, 02:08:37 pm
content: Quote from: bsalai on December 21, 2016, 10:43:58 amI dont know if you saw my post, but Mouser has some that are close enough where you can order just one each, or several of each like BFX said so you can ohm them and get the ones that are the closest. Wherever you get them from they need to be 1/2W 1%.Quote from: Fisher77 on December 21, 2016, 12:05:53 am

author: bsalai
author_rank: Regular Contributor
timestamp: December 21, 2016, 11:54:02 pm
content: I did, thank you very much. I was actually trying to figure out the wattage I should get. The ones I removed are literally toasted, so no clue there, or on the parts list. In the photo of the good unit, one looks substantially bigger than the other. I was considering getting four surface mount resistors of each value and stacking them up, two in parallel in series with two more in parallel. That should handle the power easily don't you think?Sent from my iPhone using Tapatalk

author: Fisher77
author_rank: Regular Contributor
timestamp: December 22, 2016, 01:54:56 am
content: If it were mine, I would stick to through hole. And they definitely need to be 1/2 watt.

author: bsalai
author_rank: Regular Contributor
timestamp: December 22, 2016, 06:50:11 am
content: Thanks, I will do it that way. I really appreciate all your help with this.Sent from my iPhone using Tapatalk

author: Fisher77
author_rank: Regular Contributor
timestamp: December 22, 2016, 07:38:59 am
content: No problem, glad to help. Let us know how it turns out.

author: bsalai
author_rank: Regular Contributor
timestamp: December 24, 2016, 12:13:23 pm
content: I've ordered the parts and am waiting. Probably next week. I'll certainly let you know how it goes. Thanks again.Merry Christmas.Sent from my iPhone using Tapatalk

author: pyroesp
author_rank: Regular Contributor
timestamp: December 24, 2016, 02:41:06 pm
content: Why not have a resistor that almost matches and then put a 10-turn pot in parallel to "tune" it to the right value ?

author: bsalai
author_rank: Regular Contributor
timestamp: December 29, 2016, 11:43:22 pm
content: Well, the parts came, and I installed them. I am rigging up some resistors to test the current ranges. Unfortunately I don't have a reference so let's hope Ohm was right!Sent from my iPhone using Tapatalk

author: bsalai
author_rank: Regular Contributor
timestamp: January 03, 2017, 05:55:11 pm
content: Thanks to everyone for the helpful suggestions. The meter is back together and functioning. I haven't been able to find calibration instructions, does anyone know how, there seem to be only 3 pots plus a couple is sliding taps on the high current shunts. Any suggestions would be helpful.Also, I have a few of each of the resistors I replaced led over. If anyone has a similar repair, you would be welcome to a set of them.Happy New Year.Sent from my iPhone using Tapatalk

author: Fisher77
author_rank: Regular Contributor
timestamp: January 06, 2017, 04:15:07 am
content: I have looked on the net, but have yet to find any calibration procedures for it. As far as the high current shunts, I would not move them at all.

author: bsalai
author_rank: Regular Contributor
timestamp: January 06, 2017, 09:35:07 am
content: I found calibration info for the 269 that might be what we are looking for.http://www.simpson260.com/downloads/tb9-6625-2352-35.pdfThe drawing showing the pc board layout and calibration pot position looks right. I might give it a try.Sent from my iPhone using Tapatalk