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Buzzing Voltage Regulator

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VanBuren
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Oct 22, 2014, 4:17 AM

Post #26 of 76 (1620 views)
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Re: [jts1957] Buzzing Voltage Regulator [In reply to]	Can't Post

Thanks. I'll continue tomorrow. I did locate IC501 so, if C507 is there, I'll find it. The markings are very clear on both sides of the board, so there is no mistaking numbers. If it's there, I'll find it. I can locate just about all of the other numbers you mentioned. Logically, I can see no reason for it C507 not to be there but my knowledge of the electronics is limited to knowing what the part numbers mean. C=Capacitor, R=Resistor, J=Jumperl, etc. and that's where it ends, but it does help. Thanks again.

jts1957
Veteran

Oct 22, 2014, 6:48 AM

Post #27 of 76 (1619 views)
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Re: [VanBuren] Buzzing Voltage Regulator [In reply to]	Can't Post

Quote

Photo of FOIL side of pins of IC501? (LA7838 hopefully). Also yoke plug joints?

You never did report/reply to this.

-------------------------
Location: Far, Far Away

VanBuren
New User

Oct 22, 2014, 4:45 PM

Post #28 of 76 (1610 views)
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Re: [jts1957] Buzzing Voltage Regulator [In reply to]	Can't Post

I'm working on that. I just got back with new batteries for my camera. Then I have to do the ImageShack routine.

VanBuren
New User

Oct 22, 2014, 6:32 PM

Post #29 of 76 (1590 views)
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Re: [jts1957] Buzzing Voltage Regulator [In reply to]	Can't Post

https://imagizer.imageshack.us/v2/616x462q90/r/538/vFnjIl.jpg

VanBuren
New User

Oct 22, 2014, 7:34 PM

Post #30 of 76 (1583 views)
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Re: [VanBuren] Buzzing Voltage Regulator [In reply to]	Can't Post

For some reason the pics won't post to the forum. I don't know why, since I am following the directions to a "T" and the same ones worked last night, so I am baffled but I will keep trying.

VanBuren
New User

Oct 23, 2014, 3:35 AM

Post #31 of 76 (1568 views)
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Re: [jts1957] Buzzing Voltage Regulator [In reply to]	Can't Post

http://i48.photobucket.com/albums/f223/Bakereighty/002_zps942c1d4e.jpg?t=1414031415

VanBuren
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Oct 23, 2014, 3:43 AM

Post #32 of 76 (1566 views)
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Re: [jts1957] Buzzing Voltage Regulator [In reply to]	Can't Post

http://i48.photobucket.com/albums/f223/Bakereighty/002_zps942c1d4e.jpg?t=1414031415

jts1957
Veteran

Oct 23, 2014, 4:27 AM

Post #33 of 76 (1554 views)
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Re: [VanBuren] Buzzing Voltage Regulator [In reply to]	Can't Post

Quote

IC501? (LA7838 hopefully).

NOT! "I better get another hat."

What is part number on IC501 face?

-------------------------
Location: Far, Far Away

VanBuren
New User

Oct 23, 2014, 5:19 PM

Post #34 of 76 (1547 views)
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Re: [jts1957] Buzzing Voltage Regulator [In reply to]	Can't Post

The number is 7841 and under that number is 8v 9. There are seven terminals. Again, I cannot find C507. On another note, were you able to see any further pic?

VanBuren
New User

Oct 23, 2014, 6:32 PM

Post #35 of 76 (1543 views)
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Re: [jts1957] Buzzing Voltage Regulator [In reply to]	Can't Post

[URL=https://imageshack.com/i/p8QPzDtmj]

[URL=https://imageshack.com/i/ipnE4XzZj]

[URL=https://imageshack.com/i/ey2GayDAj]

[URL=https://imageshack.com/i/ipKwoLy0j]

[URL=https://imageshack.com/i/exJw2gI9j]

jts1957
Veteran

Oct 23, 2014, 10:23 PM

Post #36 of 76 (1539 views)
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Re: [VanBuren] Buzzing Voltage Regulator [In reply to]	Can't Post

I can see everything that is a valid picture or address to a picture.

Remember to bring ANY discrepancies to my attention ASAP. IC501 info I gave before was based erroneously on a LA7838 13 pin IC when you ACTUALLY have a LA7841 7 pin IC.

I'd like a picture please, looking straight down over IC501, showing the location numbers of components inside the white line boarders of the area labeled: V-OUT.

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Location: Far, Far Away

VanBuren
New User

Oct 24, 2014, 4:31 PM

Post #37 of 76 (1534 views)
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Re: [jts1957] Buzzing Voltage Regulator [In reply to]	Can't Post

[URL=https://imageshack.com/i/pbvMyESHj]

[URL=https://imageshack.com/i/f0tfRRrHj]

[URL=https://imageshack.com/i/p4K6WVCFj]

jts1957
Veteran

Oct 24, 2014, 8:01 PM

Post #38 of 76 (1529 views)
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Re: [VanBuren] Buzzing Voltage Regulator [In reply to]	Can't Post

I'd replace these parts, if one-by-one, in this order: C502, D501 & IC501.

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Location: Far, Far Away

VanBuren
New User

Oct 24, 2014, 8:22 PM

Post #39 of 76 (1525 views)
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Re: [jts1957] Buzzing Voltage Regulator [In reply to]	Can't Post

OK, I'm on it and I'll be back. It'll take a little time, but I'll give you a blow by blow. Thanks

VanBuren
New User

Oct 25, 2014, 3:51 AM

Post #40 of 76 (1521 views)
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Re: [VanBuren] Buzzing Voltage Regulator [In reply to]	Can't Post

Just curious, can any of the devices you mention be tested on the board with a multi-meter?

jts1957
Veteran

Oct 25, 2014, 4:49 AM

Post #41 of 76 (1520 views)
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Re: [VanBuren] Buzzing Voltage Regulator [In reply to]	Can't Post

Doubtful your defect would show with a meter. Freeze spray on the diode or IC maybe would affect?
Cap is easiest to change, next would be the diode, and lastly the IC. IF it is none of those, it's 'back to the drawing board.' Wink

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Location: Far, Far Away

VanBuren
New User

Oct 25, 2014, 3:46 PM

Post #42 of 76 (1517 views)
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Re: [jts1957] Buzzing Voltage Regulator [In reply to]	Can't Post

OK. I don't expect to have a problem putting the new components in. I'm going to order the parts on line, so it will take me a couple of days to get them. Where I live (Arkansas) the sources are very limited, so I feel more confident in just ordering them on line.

VanBuren
New User

Oct 25, 2014, 8:36 PM

Post #43 of 76 (1510 views)
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Re: [VanBuren] Buzzing Voltage Regulator [In reply to]	Can't Post

I was able to get these. Perhaps with your experience you can analyze them better than I could. They are hard to read and when I tried to blow them up, they became so distorted I could not read them at all. Basically, I was able to ID the part number for D501 and IC501. I cannot find C502 on any of the parts lists but I am able to physically read it on the board.[URL=https://imageshack.com/i/eyHJ4e57j]

[URL=https://imageshack.com/i/id7BLdklj]

[URL=https://imageshack.com/i/hltJSjCUj]

[URL=https://imageshack.com/i/idtluv44j]

[URL=https://imageshack.com/i/f02zsGGSj]

[URL=https://imageshack.com/i/exSutWSvj]

[URL=https://imageshack.com/i/p5RGRlp8j]

[URL=https://imageshack.com/i/idrfCOJnj]

jts1957
Veteran

Oct 25, 2014, 10:00 PM

Post #44 of 76 (1508 views)
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Re: [VanBuren] Buzzing Voltage Regulator [In reply to]	Can't Post

Check your PM.

Common capacitors NOT listed. Value / Voltage / Temperature should all be on the part. Best to replace like with like, but if you must, you can go up a step on each.

-------------------------
Location: Far, Far Away

VanBuren
New User

Oct 26, 2014, 2:41 AM

Post #45 of 76 (1499 views)
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Re: [jts1957] Buzzing Voltage Regulator [In reply to]	Can't Post

The diode was the main issue because I could not pick up any value without cutting it off the board and then too, maybe there isn't anything written underneath, so I pursued the 4147. I was able to get a one day look for $8.99 from Scripd.com. It's the same that Sams offers directly for $22.00. I obtained my objective by getting a number off of the parts list. Unfortunately, as I wrote previously, the C502 is not listed on the capacitor list and I sent an e-mail to Scrid questioning that the material is complete.

jts1957
Veteran

Oct 26, 2014, 4:00 AM

Post #46 of 76 (1491 views)
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Re: [VanBuren] Buzzing Voltage Regulator [In reply to]	Can't Post

Important Parts Information

> The parts listed here are those not usually available from a well-stocked supply cabinet or bin. That would INCLUDE C502

Schematic photos number 4 & 5 are duplicates.
Legibility is due to them being photos (jpeg), NOT pdf (as Sam's Photofacts supplies).

Diode D501 can be any of: ERA15-02 or MPG06G or S5277B or 1N4002ID (possibly only part of number will appear on actual part).

IC501 is LA7841

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Location: Far, Far Away

(This post was edited by jts1957 on Oct 27, 2014, 4:40 AM)

VanBuren
New User

Oct 26, 2014, 5:51 PM

Post #47 of 76 (1481 views)
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Re: [jts1957] Buzzing Voltage Regulator [In reply to]	Can't Post

I have the parts spotted, at one source or another. There is one place in the area we live in that I am going to visit tomorrow to see what he can do for me. We are from the North (New Jersey, New York area) and have realize that the sources like we had there do not exist here in Arkansas, so we have to do a lot of on-line purchasing.

VanBuren
New User

Oct 27, 2014, 4:21 AM

Post #48 of 76 (1471 views)
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Re: [jts1957] Buzzing Voltage Regulator [In reply to]	Can't Post

I heard from Scripd, the people that I got the SAMS from and apparently, the information is maintained by another party. The game me the option of getting my money back so I agreed to that. Apparently what I got is all I'm going to get.

jts1957
Veteran

Oct 27, 2014, 4:39 AM

Post #49 of 76 (1468 views)
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Re: [VanBuren] Buzzing Voltage Regulator [In reply to]	Can't Post

Read posts #44 & #46 AGAIN!

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Location: Far, Far Away

(This post was edited by jts1957 on Oct 27, 2014, 4:48 AM)

VanBuren
New User

Oct 27, 2014, 11:52 PM

Post #50 of 76 (1457 views)
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Re: [jts1957] Buzzing Voltage Regulator [In reply to]	Can't Post

I ordered the parts today and they should be here in a couple of days. I got what I wanted with no subs or differences. Where I live, there is a complete absence of a real electronic distributor. Actually, nobody gives a damn. By the way, I was able to download the schematics and documents from that file I had access to for a day. The PDF, as you say, is much more clearer than the photos.

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