View Full Version : Sencore VA-48 repair...HELP!


nasadowsk
01-26-2008, 04:49 PM
Ok, I got a VA-48, and the signal output is dead (not the RF one - that works). Now, i called up Sencore and asked if they had a schematic. They do but -get this - they wouldn't send me a copy of it "Because it won't fit on out copier, sir". I wish I was joking.

Anyway, the small circuit board under the chassis with the two thin heat sinks - there's two wasted resistors that burnt - R2 and R6. i need the values of these two resistors.

Apparently, TR 8 and TR.6 died, but I've got those vlues. and TR 3 los suspicious.

Anyway, if anyone's got a VA-48 schematic or can pop the lid off the bottom of theirs and tell me what R2 and R6 are, it'd help me out a lot.

thanks! :)

radiotvnut
01-26-2008, 05:25 PM
I'll dig mine out and open it up and see what those resistors are.

So, the schematic wouldn't fit on their copier! That's a new one! They just want to sell you $20,000 worth of new equipment and don't want to be bothered with the old stuff!

grimer
01-26-2008, 11:01 PM
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nasadowsk
01-27-2008, 08:18 AM
Thanks!

podfinger
01-28-2008, 07:16 PM
Didn't think Sencore would have crappy customer service like that. They are probably just interested in selling new gear as was pointed out earlier.

grimer
01-28-2008, 07:35 PM
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nasadowsk
01-29-2008, 06:35 AM
It might be helpful - I t*think* I've got the thing debugged, but it'd be useful to have a schematic anyway...

nasadowsk
02-01-2008, 09:07 PM
*sigh* Looks like I almost have it, but it's clipping at the extremes of the minus scale. Actually, a good chunk of it. You got that schematic handy, looks like I need it afterall :(

grimer
02-02-2008, 12:22 PM
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nasadowsk
02-02-2008, 04:17 PM
Thanks! :)

Looks like I might have another suspect semi on there. At 10 cents a pop or less, I just bought a baggie of all of 'em.

But it looks like it'll work, and actually as of now it's semi-useful anyway. Right now, the main signal generating board's the last thing I need to worry about (it's as good as you'd expect for a dirty dusty board), so if you need a scan order, that guy's last.

Looks like Sencore's 'lifetime' support is about as goos as Tektronix's. Lifetime till they decide it's not... :mad: