Tube Amp Archive

Don't have a scope unfortunately. And wouldn't kno how to use it even if Si would have one

martin manning wrote:Like this:

Yes, but do I need the other jumper under the board then? It's either or, isn't it?

Just to be clear, the J. Border PCB is a bit different from the traditional relay board since it is made to handle any of the relay duties on the amp. The OD relay must be jumpered as shown but you only have to use one jumper, either or. The black dotted line that goes diagonal, would be an under b...

Will do. Thanks

CHIP wrote:

ToneMerc wrote:Do you have the NC jumpered to the NO terminal?

TM

That's the problem, if the eyelets empty.

Oh. I forgot to jumper NC to NO... Fixed now but can't hear any difference. Back to checking my wiring I guess

Could somebody please double check for me that I wired the relays correctly. I'm using the PCB's from agbamplifiers http://agbamplifiers.com/pcb/UNIVERSAL%20RELAY%20APP%20NOTES.pdf Relay 1 (preamp boost) [img:1024:764]http://i638.photobucket.com/albums/uu104/lionaird/3ccd368d.jpg[/img] Far left wire...

Try this, Set pre amp vol. to 1 o'clock,the drive(level) 11 o'clock, the volume(ratio) to approx. 1 o'clock. set the trim(trigger) to approx. 23k ohms from wiper to ground. Then adjust the volume(ratio) pot to try and match clean volume and OD volume. If you adjust the drive(level)for more or less ...

Try this, Set pre amp vol. to 1 o'clock,the drive(level) 11 o'clock, the volume(ratio) to approx. 1 o'clock. set the trim(trigger) to approx. 23k ohms from wiper to ground. Then adjust the volume(ratio) pot to try and match clean volume and OD volume. If you adjust the drive(level)for more or less ...

Hi everyone, I have a big volume discrepancy between the clean and the OD channel of my #183. Now, I can adjust the 100K OD trimmer and it does change the volume. But the clean channel is still much louder, even when I set the OD trim to 0 Ohm. That's not how it's supposed to be, is it? :? Cheers, T...

I got a light bulb limiter actually. Used it for the initial startup but really should use it again...

I think the problem are the two 330uF electrolytics. When I switch the amp back into standby after like 2 seconds then there is a hissing noise coming from the caps...

Well, I have no idea what's going on. I got rid of the 50/100 switch. I put a new choke in. I tried a different set of tubes. I disconnected the feedback wire which goes from the impedance selector to the preamp board. But as soon as I switch the amp out of standby, the choke heats up within seconds...

Clearly some unknown "event" damaged the screen resistors, and could have damaged the choke as well. Maybe the half-power LED, too. It will be interesting to hear how this build sounds- the lead dress you have is very different from the the usual D-practice. Well, I played it for a couple of minute...

All indications are that something is shorting. Screen resistors fried, choke fried. I would put my stakes on the powersection/tubes. So it could be the power tubes? It's a brand new set though... Maybe,but I would start to measure all parts in the dropping string.(amp off), resistance from all tub...

erwin_ve wrote:All indications are that something is shorting. Screen resistors fried, choke fried. I would put my stakes on the powersection/tubes.

So it could be the power tubes? It's a brand new set though...

Not over yet. My choke (Classic Tone 90mA DC, 4Hy) just fried itself (as in started smoking). I have a spare Hammond choke with the same specs as a replacement but obviously need to fix the problem first. Any idea what could have caused that?