65 Ampeg Reverberocket R-12Ra trem ticking noise

[lexluthier72]

Hey all. I recently picked up a Reverberocket R-12-Ra. The trem is ticking when the intensity pot is at 3. It is in time with the speed control. I can get it to stop ticking by adjusting both trem controls somewhat. In my readings on the interwebs, my amp does not exactly match the schematic. Im a bit stumped. Trem circuits are pretty foreign to me.
-Erin

[g1]

Please post the schematic you have, and list the tubes that are in your actual amp.

[Enzo]

And tell us where the schematic differs.

[lexluthier72]

In other gut shots of r-12s I see 3 .05 caps side by side. My amp appears to not be laid out like that. I find only 2 .05s. One has been replaced by an orange drop. Im stumped as to what to do. Heres a gut shot and schematic. My understanding is Ampeg amps did often not match the schematics. My tubes are correct on the schematic

[lexluthier72]

Also, my amp appears to not have a trem module...(ES-1)

[g1]

The ES-1 is the 'echo satellite'. It is a stand-alone unit with it's own speakers in a cabinet. That's why it has a separate schematic, it was an optional unit.
https://reverb.com/ca/item/6086122-a...ite-es-1-1960s

Have you tried swapping around the trem tube with one of the other 6SL7's?

[lexluthier72]

Have you tried swapping around the trem tube with one of the other 6SL7's?[/QUOTE]

I will try this. Cool! Never seen the ES-1. Ill report back after tube swap

[lexluthier72]

Swapped 6sl7 tubes around. No fix

[g1]

Often ticking trem is related to the wire dressing. You could try moving wires around in the trem circuit area and see if you can improve it.
I kind of doubt there is any defective part as it sounds like the trem is otherwise functioning correctly?

[lexluthier72]

Ive done a bit of moving wires around to no change. It appears that next to that orange drop .05 are two crusty looking .1s Ive read on the web that sometimes they subbed in .1s in place of the .05s in the trem circuit, and that these particular caps cause havoc when they go out. ( the 3 caps next to each other) Other than the ticking, the amp is working, which is why i suspect this group of caps in the trem circuit. My next move will be to replace them.

[Enzo]

For my taste, most trems are too fast. Slowest is still faster than the slow sexy throb I want, and once you turn speed up past say 4, it is more like a buzzer than a trem. SO to slow it down, the simplest way is to increase the feedback caps. SO changing out 0.05 for 0.1 is likely. I did similar to Fenders for years.

these particular caps cause havoc when they go out.

What exactly does that mean?

[lexluthier72]

For my taste, most trems are too fast. Slowest is still faster than the slow sexy throb I want, and once you turn speed up past say 4, it is more like a buzzer than a trem. SO to slow it down, the simplest way is to increase the feedback caps. SO changing out 0.05 for 0.1 is likely. I did similar to Fenders for years.



What exactly does that mean?

Ive read all kinds of things from ticking, to no trem at all. Im still stumped as to why it is ticking...ugh.

[Jon Snell]

It is ticking because your Colpitts Oscillator is not producing a clean sine wave or the output valves are misbiased.
Check the wave form of the vibrato on the intensity pot. You are looking for a clean ish sine wave. Any spike and it will tick.

Replacing those old smoothing capacitors will certainly help a lot.

[lexluthier72]

It is ticking because your Colpitts Oscillator is not producing a clean sine wave or the output valves are misbiased.
Check the wave form of the vibrato on the intensity pot. You are looking for a clean ish sine wave. Any spike and it will tick.

Replacing those old smoothing capacitors will certainly help a lot.

Hi Jon. My bet is on the output tube bias. Thank you! I will look into this.

[lexluthier72]

It is ticking because your Colpitts Oscillator is not producing a clean sine wave or the output valves are misbiased.
Check the wave form of the vibrato on the intensity pot. You are looking for a clean ish sine wave. Any spike and it will tick.

Replacing those old smoothing capacitors will certainly help a lot.

Amp has vary-bias oscillator. Power tubes are cathode bias.