rocket with tremolo circuit?

[pleasantbullet]

I plan to implement the tremolo in my express this week. If all goes well , I'll post some clips.

thanks Hans for experimenting with this!

[hans-jörg]

I plan to implement the tremolo in my express this week. If all goes well , I'll post some clips.

thanks Hans for experimenting with this!

Great, than I could compare - at least. Looking foreward!

Best
Hans-Jörg

[pleasantbullet]

So ive put the tremolo circuit in my express but I'm not sure what is going on. It doesn't seem to be working. When I engage the foot switch nothing happens. And pots don't seem to do anything.

One side effect is with the tremolo circuit in place, the tube run super hot almost double at 80mA.

And the b+ supply is oscillating from 180v to 240 on pin 3 of v2.


Any ideas? If you see anything odd with how its wired please let me know. I've stared at the diagram for a while and can't figure it out.

The the purple wired coiled up is the connection to the bias voltage.. Its temporary til I figure the problem out.

[hans-jörg]

Hi you have a wrong poti wireing!
The 0,1 goes to Depth not to speed. And at speed the mid lug goes via 100k to ground. Pin 3 of speed comes from 10n/20n junction.

See princton rev. schem for Depth and speed and so on. There is a clear view.

You have to lift the connection from LarMar to Bias cicuit and hang the depth BETWEEN.

I see the violet wire to MV. Thats ok, but you have to lift the blue one. This, comeing from bias circuit you have to put on lug 2 of Depth. You have lug 1 now connected to ground, I think.

AND this violet wire should be shortes as all wires of Tremolo circuit (what you have done perfect).

I don´t know if everything is 100% right I wrote, but follow the circuit below, controll every single connection and it will work perfect

Best
Hans-Jörg

[hans-jörg]

ok, after a 3rd look at your pics I see only the left lug of depth is wron. Not to ground (green?) but to bias (-33 VDC?)

You could put (as shown in the Princeton Rev. / Fender 6g3) an add. cap (0,02 -0,05) from 220k/0,1 junct. to ground. It is the closest point to ground at your circut. It seems to make the Tremolo "smoother". I like it.

Sorry, one more: cut the too long pieces of the wires at tube socket (anode/grid/cathode). They are comeing very close together in the middle.
The Tremolo part is very sensitiv.

Hans-Jörg

[pleasantbullet]

Hans, Thanks so much for having a look at my circuit.

I made the suggested changes and now its working perfectly.
It sounds great!

I'll try get some samples soon.

[pleasantbullet]

here's a quick sample.

I'm playing through my neck pick up, coil tapped, so you may hear single coil hum.

-alex

[hans-jörg]

Hi,

I´m glad I could help. Sounds fine.
I put today a 3mm red LED istead the 3k3//25µ at the cathode. No change in sound but now I have it visual too. One could try different LED cloures, perhaps it has an impact to sound (LED´s from 1,7V to 2,2 V should work fine. Red is 2,0 V I drilled a hole for the LED to the back panell (between the two pots) Not necessary (I don´t wanted a hole in front) to have it in front but who knows, maybe somebody wants - so don´t hasitate. Nice feature.

Iám behaveing like a small boy who gots anew toy.
But I never neither played with Tremlo nor implemented into an amp of mine

Now some palms and ...surfing !

Best

Hans-Jörg

[rooster]

Wow, Hans-Jorg, that is a very nice Princeton schematic. Where is this coming from? And congrats on your Rocket Tremolo, a first I think?

And pleasantbullet, I guess you are the first to add tremolo to an Express? That's something, too. And also something I didn't think I would ever find interesting but I dig your recording. I guess the only thing I need to hear now is a recording with the amp on '12 o'clock'? What in the world would that sound like I wonder? Also I notice a grab bag of caps in your Trem circuit, cool, nothing stopping you I see. That's what it takes sometimes.

Great work gentlemen, and a special kudos to Hans-Jorg for pursuing this and also dogging the fix on pleasantbullet's tremolo. I will now refer to you as the TW Trem Guy.

[vladivlado]

Hello. For everyone who would like to integrate a one-triode tremolo into their Rocket-inspired amplifier, I am attaching some files here - both circuits are derived from other cathode biased EL84 amplifiers and - as you can see - they are nearly identical. Schematics are attached as well. Cheers!