Need some help with my VH4.(She's good to go.)

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Hey_bert_whtcha_doin_bert

Hey_bert_whtcha_doin_bert

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Ok, when I try to run the effects loop with send 2 the amp only works when send 2 is active. When I switch it off none of the channels work. Am I doing something wrong, pretty sure I have it hooked up like the manual says? To make matters worse the two tubes closest to the power transformer red plated on me while was messing with this. Are the two problems linked?

Also the power tubes didn't blow a fuse and after letting the amp cool down I tried it again and it hasn't red plated since. The tubes definitely need replaced because it's darker and looser from it. I'm taking care of that tomorrow. Would any of the preamp tubes cause this, seeing as I had problems with both? The head is new but has been sitting in the store for some of 08 till now. So it had time for the tubes to go bad from people doing demos.

Also I checked the bias and the first time it was around 50ma, then I couldn't get a reading. Switched DMM's and one side was 33-35ma(yellow wire) then the other was 67(blue wire). Checked it one more time for good measure and the yellow wire side was 64-66 and the blue wire side was at 66-67, so it normalized, kinda weird. I guess the tubes were kinda self healing or maybe the phase inverter is going out? But at the same time what would that have to do with the loop though. If someone can, could you take a pic of how the cables are connected on your loop for send 2 series operation. Should just be one cable going into the send 2 and one going into the series return shouldn't it?


Need help quick, have show Saturday.


Thanks,

Nick
 
The problems aren't linked normally.

The bias-issue sounds like one tube is dying.
And yes, from send 2 to the series return.
 
Oke doke,

What might cause the problem with the loop then? I have it hooked up that way. The amp will only make sound when the loop(send2) is activated, when the cables are in it, if no cables are in it the amp works normally. No other channels work if send 2 isn't on when something is in the loop.

Thanks Olaf,

Nick
 
Lets wait for Peter.
I had a VH4 years ago and don't remember too much of that switchable loop actually . . .
 
Please post your serial number - could be a chip-issue of course. Peter will ask you for it anyway.
 
serial number is 080 1037 the 1 might be a 4, close call on that.

Thanks buddy,

Nick
 
With the amp being dead when the Send 2 isn't on I presume thats completely normal, it does exactly the same on my VH4 and has done since I bought it 5 years ago, it is because you are running out of send 2 and back into the serial loop, if you had it back into parallel loop running out of send 2 (but not switched on) then you would have your guitar signal but not the effects, the effects would come in when you switch send 2 on

Remember the signal goes into the amp, out of the effects loop, into the effects and back into the amp, if the route to the effects is switched off then the amp would be dead in serial mode

I got around this by running some effects in paralled through send 2 and back into the parallel and some into the channel inserts, all midi controlled and worked great for me, not ideal but unless you buy some expensive rackmounted midi switcher units (presumably for stomp boxes going into the loop - if you have rackmount gear you can switch the effects off) I can't see another way around it

Hope this helps

:)
 
Send 2 works only with the parallel return since 1993 :yes:
What does the English manual say ?

You had a tube short on one of the two power tubes.
Sometimes it works again after the tubes cool down,
sometimes the issue starts again. In this case You should
replace the power tubes and rebias it.

Best,

Peter
 
Thanks Peter and Musemark!

Yeah, in the manual it just states to choose which return you want to use. There's no mention that the send 2 only works with parallel return.

Thanks again,

Nick
 
Alright! She's golden again. Thanks for the help guys. New tubes, biased, and got a switchable loop now.
 
Hey_bert_whtcha_doin_bert":yvn2jwaf said:
Thanks Peter and Musemark!

Yeah, in the manual it just states to choose which return you want to use. There's no mention that the send 2 only works with parallel return.

Thanks again,

Nick
Click to expand...

Ahaaa ........ I will take a look into :gethim:
 
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