relaise swiching on ODS 124

[hans-jörg]

Hi Gents,
I finalised a D*Clone.
But I´m not sure about the Channel and PAB swiching because there are so different layouts about.
Wich one is realy the latest, I mean :not wrong?
I´m afraid that my tonestack is not correct wired, because I get a lot of hiss while turning the Master on. On s 0 is nothing - on 10 is hauling wich I can manipulate by tonestack.
Is there any layout on wich I can trust. I mean I found a newest one but there was still a failure wich was discussed weeks before on the relaise.
Thanks for help in advance

Hans-Jörg

[talbany]

Hans..
What is it about the relay switching in this layout that you makes believe wrong or how can I help..
Posted 124 in the files section..

https://tubeamparchive.com/download/file.php?id=11313


Tony

[hans-jörg]

Hi Tony,
sorry if I found the wrong words. I´m austrian
what I meand is that there been several discussions about wron wireing especially on PAB. I guess it was grounding. So I had there problems in the beginning with swiching.
In the end I had the ectract of 3 or 4 layouts builded up in one. So it works now, but with a disgusting hiss or low frequence humming wich gets louder while turning Master louder. Therefore I want build tonestack a second time but on 1 layout only. And the def. right one. I mean this one wich has your approbation.
So I think this one above ist this right one.

Thank you

Hans-Jörg

Edit: I see on the layout above, that on PAB relay swich the pin 2 from one side (goes to treble pot pin 3) goes on pin 3 on the other side of the relay
On the other layout for 124 ( 124 Low Plate Classic)
there is no connection to pin 3 of the second side of the relay. Both pin 3 are n.c.

[talbany]

Hans
Yes I see what you are saying and I now remember the PAB discussion issues..I remember correcting the problem w/PAB then sending it to IC to post but it never left my out box therefore was never revised on the 124 thread..I know this revision took place since I used the same layout just edited to the low plate classic and the Ford 102 amp..You can take a look at either of those as they are correct ... I will send another copy of the revision to IC again and hopefully he will change it this time..
The relay OD switching for the low plate classic/124/102 are all correct I just took a look...Thanks for reminding me on the PAB I blew it off

Sorry you are still having problems.. Sounds like something's not wired correctly...Good Luck

Tony

[hans-jörg]

Thank you for this answer. I thought I´m crazy.

ok. so I´ll follow in case of PAB Relay the R.F 102. Then I´m on the secure side.
I think I hve some wireing problem too. therefor I´ll build the Relaysection new and compare my wireing with yours. Than it will work as I expect.
Thank you
and greatings from Vienna - there is now one Dumble more on this planet - and that is good. This Amp, concerning the sound, is the best one, I builded.
When its finish, I´ll place a picture - from outside.

Hans-Jörg

[bluesfendermanblues]

Hi Gents,
I finalised a D*Clone.
Hans-Jörg

Hi Hans Jürgen,

Nice build - I can see we both use the same Chassis supplier - Tube Town - am I right?

[hans-jörg]

Jep, you are right.
Tube Town is a fast supply for Amp builder in Germany, Austria and Swiss.

Hans-Jörg

[bluesfendermanblues]

Jep, you are right.
Tube Town is a fast supply for Amp builder in Germany, Austria and Swiss.

Hans-Jörg

And Dumble city, Denmark

[Harald.Nowak]

Hi Hans-Jörg!
Great you finished a Dumble build and you like the sound; I'm also based in Vienna and would be interested to hear it first hand - if you would be willing to show it to me.
I can offer a "Bassman OD" for a test drive - this is how I call my build wich basically is a Bassman (think low plate) with optional channel chaining (and paralleling as well) and some Dumble "genes" (like 40M Feedback on V1b, 220k/500pF grid stop on V1b, snubbers on V2, 4.7u bypass on V1&V2, etc. you get the idea.); if you'd like to get in touch let me know.

[hans-jörg]

Hi Hans-Jörg!
Great you finished a Dumble build and you like the sound; I'm also based in Vienna and would be interested to hear it first hand - if you would be willing to show it to me.
I can offer a "Bassman OD" for a test drive - this is how I call my build wich basically is a Bassman (think low plate) with optional channel chaining (and paralleling as well) and some Dumble "genes" (like 40M Feedback on V1b, 220k/500pF grid stop on V1b, snubbers on V2, 4.7u bypass on V1&V2, etc. you get the idea.); if you'd like to get in touch let me know.

Hi Harald,
Isee that I have the same "feathers" on mine. Bassman is very interesting too for me. The only thing is that I´M still not finished (see above). I´m still on debuggung. Want say, as long its not finished (for me) incl. headshell, I´m not ready for shareing
But its great to know about a Dumble fan so near. Give me a bit mor time to get in touch with you (to find out what my next project could be - a bassman is on my long list ) The second is that I´m still close to "building (painting) by numbers" - means I´m not shure my builds are very helpfully to yours. Without the accurate layout of Talbany and others here in the forum, I would´nt be able to build this Dumble.

Thank you all

Hans-Jörg

[Harald.Nowak]

I´m still on debuggung. Want say, as long its not finished (for me) incl. headshell, I´m not ready for shareing
But its great to know about a Dumble fan so near. Give me a bit mor time to get in touch with you

Hi Hans Jörg!

Of course, no problem - contact me whenever you feel about sharing thoughts and some test driving; I can provide a rehearsal room every sunday as well for that. Happy building!

[hans-jörg]

I´m still on debuggung. Want say, as long its not finished (for me) incl. headshell, I´m not ready for shareing
But its great to know about a Dumble fan so near. Give me a bit mor time to get in touch with you

Hi Hans Jörg!

Of course, no problem - contact me whenever you feel about sharing thoughts and some test driving; I can provide a rehearsal room every sunday as well for that. Happy building!

Rehearsal room sounds absolutly great. Count on me!

I build the tonestack and the swiching now exactly like Talbanis layout - and it works great.
Only the hiss/humm by Master is still there. I found out its on V3. When I mesure with DMF the voltage I can hear that the noise almost stops when I touch grid of V3 (pin 2). I can read on pin 1 326 VDC and on pin 6 302 VDC. Kathode has 60,7 V. And at pin 2 I read 39,2 VDC. Same at pin 7.
Sombody an idea?
Thanks in advance

Hans-Jörg

[bluesfendermanblues]

I´m still on debuggung. Want say, as long its not finished (for me) incl. headshell, I´m not ready for shareing
But its great to know about a Dumble fan so near. Give me a bit mor time to get in touch with you

Hi Hans Jörg!

Of course, no problem - contact me whenever you feel about sharing thoughts and some test driving; I can provide a rehearsal room every sunday as well for that. Happy building!

Rehearsal room sounds absolutly great. Count on me!

I build the tonestack and the swiching now exactly like Talbanis layout - and it works great.
Only the hiss/humm by Master is still there. I found out its on V3. When I mesure with DMF the voltage I can hear that the noise almost stops when I touch grid of V3 (pin 2). I can read on pin 1 326 VDC and on pin 6 302 VDC. Kathode has 60,7 V. And at pin 2 I read 39,2 VDC. Same at pin 7.
Sombody an idea?
Thanks in advance

Hans-Jörg

Yes, check out the grounding of the V3/phase inverter, should be close to the speaker jacks.

[hans-jörg]

Hi,
you mean the grounding wire comeing from minus lug of the 1uF via 390 ohm? Should go to ground (chassis) on Return Jack. Right? But Presence is working. I guess somewhere a cold joint on the grid.

Hans-Jörg

[Structo]

Yes the ground from the 390R and 1uF joint to ground.