Cornet up and running again.

pretzel_logic · « **on:** 11 Oct 2003, 12:26 pm »

I replaced the tranny in my Cornet yesterday, fired it up with no tubes and didn't blow a fuse. I had checked the resistance in the secondaries and compared between the blown and new tranny. Very low resistance in the reds compared to the new one. I put in the tubes and fired it up again, replaced the rec tube with an NOS GE. All the tubes lit up so I checked voltages and all were within 2 or 3 volts of the schematic. Hurray!

Hooked it back up into the system and after letting it warm up for an hour played a couple LP's before the Cubs game started. Didn't give it a serious listen but it works and sounds wonderful. Now time to burn in again.

Thanks to all who helped me with this, I learned quite a bit on diagnosis and that always helps. BTW, I left in the original diodes after comparing them to a new set. Don't know why the tranny went but hope this one holds up.

Thanks again,

Brian

Braden · « **Reply #1 on:** 11 Oct 2003, 07:57 pm »

I as well would like to thank everyone for the help they gave me. Yesterday I installed the new transformer and now my Cornet is back to perfect working condition! However, this moring I was excited to put on a record, but the right channel in my CJ MV50 amp wasn't working! The EL34's are lit up, but they are not hot. I have no idea where to start with this problem! This is going to be a whole other ball game, I can tell. When will it stop? I just want to listen to a #@%* record.

Braden

pretzel_logic · « **Reply #2 on:** 11 Oct 2003, 09:55 pm »

Did you check all the connections/interconnects, speaker terminal possibly loose at the amp or speaker? Do you have any other source to check it with?

Brian

Braden · « **Reply #3 on:** 11 Oct 2003, 10:21 pm »

Brian,

I tried switching tube, IC's, speaker wire, to no avail. There don't seem to be any loose connections on the amp terminals, plus I had not touched the amp since last night, when it was working fine. There must be something broken in the circuit that lets enough power go the the input/output tubes, but broke the audio connection. Either way I guess I'm going to have to take the board out of the chasis, which means unsolderinga good dozen wires.

Braden

Braden · « **Reply #4 on:** 12 Oct 2003, 10:35 pm »

Anyways, I figured out the problem with my amp. The plate fuse on one channel was gone, but the LED light didn't come on to let me know that. I guess the circuit allows enough power to allow the pilots to come on in the tubes. The easy test, which I didn't think of at 2am when I was pulling my hair out, is to switch fuses between the channels and see if the problem follows.

Summary: Fuses are beginning to annoy me.

Braden

pretzel_logic · « **Reply #5 on:** 13 Oct 2003, 02:16 am »

Glad you found the problem. Let's hope both are units keep working but it sounds like just a fluke thing with the tranny's. My Cornet worked fine last night and sounded even better.

Brian