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4230 DOA Amateur Needs Help

looks like beep test is on diode test ..mine is on 200 ohms setting so not sure if it works the same ..
did you test the rectifier diodes yet ?
 
Have not checked them, as I don't know where they are exactly, as I said, I am quite green when it comes to repair. I can disassemble clean, lube and replace caps, but troubleshooting and repair are things I am just learning. Thanks for your patience and help. Rich

Cosmetically, cleaned up good, now if we can just get it to work!

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Cleaned, de-oxit and replaced the remote speaker switch. Rich
 
Richs_Trains said:
how do I test it?
Click to expand...
this is how it looks inside ....you need to remove the wires first ....
bridge-rectifier-shunt-before.png
 
checking the diodes on the PS all seem to have a reading one direction and 'OL' the other except H809, which seems to have a reading both directions. All were checked while in circuit. Thanks Rich
 
there is no + with ac ..or - come to that .. but yes ac from transformer then + to positive cap and - to negative cap .. lift one side of H809 and test again
 
I would also look at the AC wiring from where it comes in from the back panel, maybe it's shorted back there somewhere too! Look at the power switch as well, I've seen some pretty poor replacements done and maybe there's an issue there. I have been assuming the bright bulb is only with the power switch on, right?
 
Thank you for chiming in Randy, Tom and Beamer, unfortunately, I'm going to have to take a break from working on these units. About 2 months ago I started having a problem with my fingers and getting little blisters all over. Went to the doctor and he said it is eczema (60 years old and never have had any eczema), and he gave me a steroid treatment for it. Well, since then is has faded with the medication and raged back whenever the medication stopped. Right now I can hardly touch anything, typing hurts. I don't know if the components I have been handling caused the problem, but it is the only major change in my lifestyle in recent months. Lately I have worn exam gloves when replacing components, but it has not changed things. I am waiting for a referral to a dermatoligist and hope to get the full use of my hands back soon. I will restart the thread when I am able. Thanks for all the help and encouragement on AK. Rich
 
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Oh man! Sorry to hear this Rich! Especially as I'm 59-3/4!! Like you need any more trouble too. I doubt it's the stereo work and wouldn't doubt it's stress related. Here's to hoping the derm doc has some good solution(s) for you.
 
Randy, did try the DBT with the switch off, no light, no draw, also the power switch is original and feels OK in it's operation. Thanks Rich
 
Thanks Randy, hoping it's not all the components I've been handling, but then it's most likely stress and that's not going away any time soon. Hope to be able to check the diode in question and the rectifier in the next few days. Rich
 
Hope your dermatologist finds the issue and you will be feeling better soon. I don't think you have a capacitor allergy.
 
Sorry to hear about the problem. I hope the docs can get to the bottom of it and get you back to the workbench again soon.
 
Thanks guys, AK is really therapy for me and fixing these units is my form of 'getting away'. It's nice to have a 'community', even if it's in the cloud.

Just a couple questions so I can plan my next moves when able. The transformer has 2 yellow wires to the PS board and two orange to the rectifier. If I disconnect the rectifier to test it, can I DBT to see if the short is in the PS board or beyond, and can I disconnect the yellow leads to the PS board and reconnect the rectifier and amp boards and DBT to see if the short is there? Just trying to use my limited troubleshooting skills to narrow where to look. Thanks Rich
 
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