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TAM Power Supply repair
Posted by: techknight on 2015-06-06 17:59:52
Got a couple of these power supplies in. Both dead. one of them had 5V standby, the other one does not. 

Both have good fuses. 

This post is about ONE, as I only got the parts for one so far. 

Basically, if your fuse is good, but your missing your 5V standby, IC1 is likely shorted, and R4 blows open when IC1 shorts. R4 is the fusible resistor to IC1, and IC1 is a self-contained chopper mosfet, and SMPS controller designed specifically for standby power supply output. 

These ICs are discontinued, so you gotta scour ebay for NOS supplies. 

After changing out those components, the power supply fired right up. no problems. 

20150604_150647.jpg

20150604_150707.jpg
Posted by: Macdrone on 2015-06-06 19:07:24
Great Job.  Thank you for posting.

I am finding like all caps power supplies are right up there in failure now myself.  

I am positive you have seen way more than I have but just restating the obvious.
Posted by: techknight on 2015-06-06 19:43:39
yea, these TAM supplies arnt quite old enough to exhibit capacitor failures. 

these are general component failures. Whether surge, or whatnot. 
Posted by: uniserver on 2015-06-06 23:11:14
awesome.  well wether it was a surge or bad design, you figured it out asap!!   good job!
Posted by: Chris1988 on 2018-01-15 12:23:29
Hello,

I know the post is from 2015, but I have the same problem and need help.

Unfortunately, I can not see wich resistor I need. The color code is very difficult to recognize.

Which MOSFET do I have to buy exactly? Can I take this?

https://www.ebay.de/itm/TOP200YAI-3-Terminal-Off-line-PWM-Switch-TO220-Power-Integrations/322246017066?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20170511121231%26meid%3D420e4efc187340319c538ab0aba6cf60%26pid%3D100675%26rk%3D1%26rkt%3D15%26sd%3D322246017066&_trksid=p2481888.c100675.m4236&_trkparms=pageci%3A6c70e94a-fa31-11e7-ba62-74dbd1809eb6%7Cparentrq%3Afb7a49d31600a887e3327c0affe85af7%7Ciid%3A1#

or this:

http://www.ebay.de/itm/TOP200YAI-Integrierter-Schaltkreis-GEHÄUSE-TO220-HERSTELLER-Power-Integrat/172883552032?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2055119.m1438.l2649

Thanks in advance for your answers
Posted by: acs.cwb@uol.com.br on 2019-06-23 18:08:32
who created this topic is of parabens, went straight into the problem, with him I think I will solve my problem, congratulations, because these same parts that are with problem in my source, thanks for the help
Posted by: Alain Lowet on 2020-04-21 09:11:46
Hello,

Because i have a TAM but no Bose station, i try to reverse engineer the colors of the wire that are on the connector to the bose unit, as you dismantle your bose unit, maybe can you tell me some information about wire colors: i already know that fat yellow is 12v, fat black,blue and green is Ground, fat red is 5v, i suppose fat white is 5v, but for the thin wire, i suppose that thin black is ground, thin red is 5v, thin yellow is 12v , as i saw on your power supply picture, can you confirm thin orange is 5v standby ? this white is 5v ?

Also, i see a blue cable going under , do you know if it is a ground lead ?

Because i don't see them on your picture, i suppose thin purple, thin grey, thin green are going to the bose board ?

It could be really helpful if you could answer even some of my questions. Thanks!
Posted by: techknight on 2020-05-04 08:40:47
I dont think anyone has that information handy, I know that I do not. 

maybe @haplain has this information? 
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