Legend Model A30

[soundguruman]

Dirty legs.... hehehe.... and that was the problem..... thanks.

Don't know why they left the legs so dirty..but soldered them in anyway.

[t'audio]

Can't seem to download the schematics for the Legend A30 that are listed here. Could someone please re-post them?

Thanks,
T.

[Mark Black]

Can't seem to download the schematics for the Legend A30 that are listed here. Could someone please re-post them?

Thanks,
T.

I'll give it a try (with slightly different name and small alteration to file size):

[t'audio]

Thanks Mark ... very much appreciated.

My A30 will live again!

T.

[bfglp]

happy days indeed, I'm so happy to se this schematics drawing.

My A30 quit working a wile back. i popped it open and the only thing that looked odd was a melted zip tie that was holding CR18 to Q12 There is also one holding CR19 to Q15 thats ok. the leads on CR18 & CR19 are blackened kind or sooty.
i could use some help here I'm an excellent parts changer but a newbie @ troubleshooting

CR18 is a diode it sits above Q12 a transistor. and is strapped to a metal bracket protruding from Q12.

found a leaky cap so a cap job is in order.

do you think a bad cap could cause a spike and burn out the diode?

[Mark Black]

CR18 is in the bias string so may well be a "dual diode". When checking with a meter set to "diode check" you might see about 1.2V (or possibly more) in the forward direction. Some meters can't read the drop across two junctions - so it might be OK unless it reads shorted.

Some older components get a dark tarnish on their leads over time, so that may be normal (or not) - may have to resort to actual troubleshooting.

Bad filter cap cause a spike? Well probably not impossible but more likely the conductive goo leaking out of it might be causing problems.

What happened when the amp quit?

[bfglp]

it lost sound. tubes are fairly new i put new caps in and have very little sound @ high volume now

[Mark Black]

Try plugging a cord from preamp out to power amp in.

[bfglp]

OK, tried preamp to power amp and no sound, but if i turn on standby i get a loud transformer hum through the speaker and no sound.

so next i tried preamp out to another amp and had sound. everything functioned except when i switched on standby there was loud humming through the speaker and no sound.

[52 Bill]

OK, tried preamp to power amp and no sound, but if i turn on standby i get a loud transformer hum through the speaker and no sound.

The loud hum is probably dc voltage being applied to the speaker. Disconnect the speaker from the amp until you know that it is safe to hook it up again. Use your meter to read dc volts across the amp output and see if there in fact is dc voltage present.

...so next i tried preamp out to another amp and had sound. everything functioned except when i switched on standby there was loud humming through the speaker and no sound.

So the problem is in the power amp. Do you know how to test a transistor with your meter?

I know that there is a lot of overlap in the forums, but why not start a new thread in the repair section and get direct advice on the power amp problem.

[bfglp]

i'm getting 2.67v dc with the standby on.

I'm not sure how to test a transistor, will have to do some research. thanks!