[bozebuttons]

I picked up a non working melos maestro
acording to owner stopped working after 25hours. every thing lights up in and out of unit . mute light switches to green in the right amount of time ,all i get is crackeling noises like static out of headphones.I am a novice at electronics
.I have schematics for unit. any Ideas that can help me out. Can I use a multimeter to test circuits. I would like to take a crack at this before sending out for repair.
And yes I put known good tubes in unit.
Thanks for any advice in advance.
Bozebuttons

 

[rickcr42]

if you have the schematics it should have voltage reading for various points of the amp.Check these operating points first.
And of course , make sure the power supply is operational and putting out the correct voltages

another method is to use a signal injector to put an audible tone into the circuit that can be monitored at the output (use cheap cans).
Start at the beginning of the output section and work towards the input section to isolate the bad section , then try to isolate the actual bad part

 

[carlo]

Hey bozebuttons,

So no sound at all even with a signal playing? Is the static on both channels? I looked at a Melos that had a similar problem in the left channel only, start with the diodes in the low voltage supply (near the top of the amp, to either side of the first heatsink).

best,
carlo.

 

[rickcr42]

check the DIY links rsource above for a link to the curcio troubleshooting guide.
might help

 

[bozebuttons]

Thanks for the info guys I appreciate it.
I will look at amp after holidays to much going on now.
bozebuttons

 

[Nikko]

Hey guys,

I have a SHA Gold Reference that I've owned since new in 1998 and I'd like to take the preamp section, sonically, as far as it'll go. I was wondering if someone here could recommend specific updates and changes that I should make to the preamp section to improve detail and lower noise? Also, I was wondering if anyone here is familiar with the capacitors from Jeff Glowacki @ Sonic Craft ( www.soniccraft.com). I've been told they're the best available and I'm contemplating sending my Melos to Jeff for the work. I'd like to save him the trouble of having to sift through schematics if anyone already knows what needs to be changed out.


Thanks!!

 

[JMT]

You might want to PM Head-Fi member (and one of the coolest dudes around) carlo, he has done some wonderous things with his Melos.

 

[bozebuttons]

Quote:

Originally posted by JMT You might want to PM Head-Fi member (and one of the coolest dudes around) carlo, he has done some wonderous things with his Melos.

Carlo has my maestro right now and is doing some extreme mods to it.