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SUPPORT FORUMS FOR ZKITS >> ZKIT 1 Support forum >> Help please.. trouble in paradise
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Message started by Ryan H on 09/24/09 at 22:46:09

Title: Help please.. trouble in paradise
Post by Ryan H on 09/24/09 at 22:46:09

Hi All,
I've been very much enjoying my Kit1 for about 7 months, everything working with splendid sound. Now things are not working. Snap, Crackle pop, increasing as the sound faded.. then... no sound. All the voltages check out within spec at the start but then quickly, the 1K (6W) resistor becomes glowing red. Then, of course, all voltages are not at all correct. I switched off at the first sign of 'glowing red'. The fuse did not blow.

Any hints as to why I'm drawing some much current? I thought, when I first heard the crackling etc, I observed a puff of smoke from the cathode bypass electrolytic.

Thanks in advance for the help. I want my lovely amp back!
Ryan

Title: Re: Help please.. trouble in paradise
Post by Steve Deckert on 09/24/09 at 23:08:48

You have a shorted output tube - most likely.

You may also have installed the bypass cap backwards too. Since it is a 25 or 35 volt cap and only seeing 10~15 volts, it can take a very long time to actually fail. If it shorted, then your tubes are seriously over biased causing the excess current draw.

Steve

Title: Re: Help please.. trouble in paradise
Post by Ryan H on 09/24/09 at 23:30:40

Thanks Steve!

Title: Re: Help please.. trouble in paradise
Post by Ryan H on 09/25/09 at 16:59:15

Hi All,
I've checked and double checked. The bypass cap was installed correctly from the beginning. My question is... is there a chance I smoked it when the output tube shorted?

I'm going to take the precautionary step and replace it as well, but I'm curious if that could be a consequence of the tube failure.

Thanks,
Ryan

Title: Back up and running
Post by Ryan H on 10/03/09 at 04:48:16

I replaced my output tubes and in the process completed the CCE mod, replaced the cathode electrolytic and put two 2k-10W resistors in parallel to replace the 1k 6 watt resistor that steps down the voltage.

All is well. I left the jumper from pins 8 to 3. This simply connects both sides of the cathode.

So I'm happy to have things up and running again. Not enough time to listen to things critically.

Thanks for the help.
Ryan