• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

Help with Juicy Music Tercel (no left channel)

B

boulderdash

Active Member
Hello, I was just given a Juicy Music Tercel SET phono pre by a friend who has had it in his closet for years unused. I just tried it out in my system and I can't get any life out of the left channel on either input, besides some static after a few minutes of warmup the first time I powered it on.

All of the tubes are warm and glowing, and I've reseated them all and swapped the 12AT7s around. I also double checked with my other preamp (UTurn Pluto) to make sure it wasn't anything screwy with the cart wiring (I have a dumb Rega and sometimes if it picks up a ground loop it will drop a channel after a while) but both were fine on that. The tubes are 2x JJ 12AT7, a single JJ 12AX7, and a GE 12X4.

I do camera repair for work so I'm pretty handy with electronics, but I've never messed with tube circuits before. I did find the schematic and some interior pics from this kit posted to AK a while back. Where should I start with this? Thanks in advance!
 
Register to hide this ad
Just be careful, there are lethal voltages inside these things! Maybe share the schematic with us as a starting point. I use a signal generator and a scope, after checking voltages, when I dive into a problem like this looking for where the signal stops.
 
IcNJMM3.jpg


dNZjjVm.jpg
1418648-ed1fe62f-juicy-music-tercel-mmmc-tube-phono-amplifier-wtelefunken-amp-amperex.jpg


I know all about high voltages, been wacked with camera flashes before, not fun. The person I got it from says it was fully working when he parked it, he just stopped using it because he upgraded to a PS Audio. It's not the end of the world if I don't get it going, but I've never had any tube gear so it would be cool to have working.
 
Looks like there is a relay between the input jack and the grid of the first tube, possibly the contacts got corroded when sitting? It looks like the relay is for choosing MM or MC, maybe bypass the relay to the type you are using to make sure the signal is getting to the grid of the first pin. Also make sure the dip switch is set to match your cart and only one type is selected. This is a pretty simple circuit once you get past all the input type choice stuff, I bet the signal is never getting to the first tube.
 
You must log in or register to reply here.
Back
Top Bottom