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Cheap Chinese 6P3P kit

The input signal is grounded to the - buss. I did put a jumper from the input ground to the chassis and it made no change. I will take better pictures give me a minute
 
pictures of the preamp

here are a few more
 

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more photos

do you see anything? I messed up on
 

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This would be Too Easy a Fix...
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T Tanner said:
Yes but look closely there are plastic insulators under them, so should I run a ground jumper to the chassis??
Click to expand...

I'm trying to be careful and not give you incorrect information. In looking at the schematic, the schematic is not clear. There are two points labeled "ch right", but neither appear to be a ground. Whenever there is a channel input jack, there is usually a center, positive connection, and the outer, or ground connection. It's very common for new RCA jacks to be shipped with a plastic insulation disk for those situations where the jack will be insulated from the rest of the circuit. If this is not one of those situations, and I would assume that it's not, then the insulating disk should have been removed before the jack was attached to the chassis.

If you have the jacks fully insulated from the chassis, and if they're not supposed to be insulated from the chassis, then you have a problem. I'd wait until someone else who is more familiar with this circuit to chime in, but I'm guessing this could be an issue.
 
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looking at the print you see the straight line thru the RCA's, this is the ground wire, you seam to be missing this on your output rca's.
also note the star grounding, one point only. it over by the PS , it can be any place, but only one point to the chassis.

maybe somebody who has posted pics of a working one can get us a pic, under the lip, of the rca's:scratch2:
 
OK I just went to the bench and ran ground jumper from both input RCA jacks to the chassis ground. I ran a jumper from the - buss wire to the chassis. and guess what???????



IT WORKS
 
T Tanner said:
OK I just went to the bench and ran ground jumper from both input RCA jacks to the chassis ground. I ran a jumper from the - buss wire to the chassis. and guess what???????



IT WORKS
Click to expand...

Sweeeeeet! RCA jacks are almost always supposed to be mounted directly on the chassis, and a ground buss must be grounded. :yes:
 
Ok time for some scotch and a cigar. WOW this nearly kicked my butt. Thanks a million guy's your the best !!!!!!!!!!!!!!!!
 
I cant stop smiling. The preamp sounds really good!!! The siliconray preamp to my Dynaco ST-70, out to the Magnapan MG II's Norah Jones never sounded any better
 
SuWeet!!...Let it Burn-In for a While...And Enjoy...Like I Said, It Does Sound Nice...
I've been working on the Gain Too. Check here..
http://www.diyaudio.com/forums/sili...e/200120-6j4-6p6-hifi-preamplifier-kit-2.html

Oh, Tanner...One Biggie that I found with Mine...It seems that the Tube Sockets have a Mind of their Own. If, out of Nowhere it All goes to Hell in a Big Way, pull the Output Leads, leave the Power on and turn the Vol. down. Then, Pull all 4 Tubes and Swap them to the Other Side. Put the Outputs back in and Listen for Silence...Repeat until there is Quietness...
 
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