B3 and 147 troubles

[enor]

Any one got the answer to these questions.

53 and 55 are missing on both the upper and lower manual .......I have cross checked the TWG and in both cases it is working. So this condition leads me to believe that the wire is broken between the TWG and the tag for the upper - the lower may still be intack but the signal is not getting through to the manuals. What else would cause this?

That's by far the most likely problem, and a quite common one too. Just run a "bypass" from the generator directly to the right terminal on the lower manual.

Also I have 79 missing on the upper only forget the (drawbar) but only on the upper. This suggests that the tag to the upper is disconnected Anything else?

Is it missing from _every_ place it needs to be on the upper? If so, probably a broken wire between the manuals

Or is it missing from one place only? If so, a fault within the upper manual.

[PGR]

Update on 53 and 55 as Enor suggested I had two broken wires at the loop point of the upper so the signal from the twg was not getting to either the upper or the lower I re soldiered them and problem fixed. I retested the 79 and actually think that as I climb the scale with the 9th drawbar pulled ithe hookup is there and the it does not sound because the caps in the twg does npt produce at the upper levels well I also had the organ playing through the guitar amp so not the best pickup It should return when I get to doing it through the amp I need to repair the amp first
So I am back on tract NOT opening the Manuls again!
on to the next phase. the AO-28

[PGR]

I am still working on the AO 28 I have left it hooked up in the organ and flipped it over on the bench next to the back bay so I can work on it. I have completely tested V3 and some of the DV volts are on the low side but close enough for what I am doing . (Chasing a 60hz hum) and no out put sound.
OK so looks like I have from V3 pin 6 says 285v and I get 275 v to input of the T3 primary - Any one know where the primary comes out? don't know where to measure it from. Also checking the secondary on both g terminals
What is the voltage range on G cant see where that is ?

[Tim_at_Jonas]

IME other than a tube, the most common cause of "no output" is a failed cathode resistor someplace.

[PGR]

HI guys,

I still have a problem with the AO-28 in the B3. I get a very uneven load generated from the G G My condition is that When sample across the GG terminals I get a reading of 2.03 /2.02 (I set the trim tab at 1.5 turns out)
This occurs when I pull the sub fundamental out to 8 , Press the volume peddle to the floor no prec and no vibrato. and press the middle C note.
Here is my issue when I test each G to ground or chassis I get a very different reading . On my Right G I get 1.02V which I expected.. but on the left G I get 5.32 V
Does this suggest I have a power loss to ground ? or a bleed somewhere - it just seems too high If you think so too please let me know and possible reasons for it.
thanks guys

[Tim_at_Jonas]

The output of the AO28 is a transformer with a grounded tap, which on the schematic appears to be a center tap. If such is the case, your unequal measurements would seem to indicate a faulty connection or a faulty output transformer.

[PGR]

Hey Tim,
Thanks for the note , I cleaned up the connections and get a much more balanced signal off the transformer - now makes me thing I need to reflow some connections in the amp too.
Does any one know what level of voltage is right for the G G terminals to produce max output through the 147 or any leslie for that matter. ? This question is designed to get at some way to measure the overall performance output for the B3 . this I guess is assuming that the greater and balanced output is going to max the organ out put and there by allow for the max amplification in the leslie. I have turned up the 147 volume control and floored the organ in a relatively small room...60ft x 20ft. ITs loud but it does not **** ** out the door. ? Im figuring it should **** ** out the door when cranked up? Ps the volume trim pot on the housing is set correctly. and full volume does not make distortion occur. Any one have some ideas how to approach this one?


ALso can someone help me find a procedure to balance the foot peddles or generally how you go about setting them up? I got some that bang really loud and some that don't . Is there a felt pad that is recommended for the underside of each bass peddle?

[PGR]

I am looking for more volume from the B3 and 147 I have compared it to the A100 and 122 when I set up the leslie 122 with a volume about 3 and play the A100 I get huge amount of sound - lots of guts But I cant come close to that when I set the 147 amp at 7 and run it through the B3
before I run out the door and buy new tubes I would like some idea of what readings I should have coming from the G G terminals on the PRe amp of the B3 Or how ever it should be tested to make sure it is producing correctly at the right ranges. If you have some input or perhaps a better way to look at this issue I open to it.

[enor]

I am looking for more volume from the B3 and 147 I have compared it to the A100 and 122 when I set up the leslie 122 with a volume about 3 and play the A100 I get huge amount of sound - lots of guts But I cant come close to that when I set the 147 amp at 7 and run it through the B3
before I run out the door and buy new tubes I would like some idea of what readings I should have coming from the G G terminals on the PRe amp of the B3 Or how ever it should be tested to make sure it is producing correctly at the right ranges. If you have some input or perhaps a better way to look at this issue I open to it.

The load resistor on the 147 is set to "open", right?

[geoffbrown]

I have C3 connected to a 122 and PR40 .I added a 147 as well, taking the signal from one of the G terminals as shown on the Hammond wiki website, the result sounds ok but with less volume on the 147
I intend to install a matching transformer in the 147 signal path so the balanced signal from the GG terminals can be converted to unbalanced signal for the 147 ,doing this should equalize the volume between the 147 and 122,I think.

Maybe this is the reason for the low volume from your 147? how is your 147 hooked up to the B3?

[PGR]

Enor the load is open on the 147

I also looked over the 147 hookup and I have Seperte line out to the 147 from each G terminal plus the ground. So I have to assume that I have both sides of the matching transformer When I was into the bottom of the PRe amp I confirmed this before. I did have some problems with cold soldier but refloated everything again
That brings me to this point.

[enor]

Enor the load is open on the 147

I also looked over the 147 hookup and I have Seperte line out to the 147 from each G terminal plus the ground. So I have to assume that I have both sides of the matching transformer When I was into the bottom of the PRe amp I confirmed this before. I did have some problems with cold soldier but refloated everything again
That brings me to this point.

Your line out to the 147 should come from one of the Gs (either one) and ground. I don't quite understand your circuit if it somehow uses both G terminals?

[geoffbrown]

If the line out to the 147 uses one G and ground then you only get half the signal hence low volume ,if both G's are used through a matching transformer then should have normal volume.

[enor]

If the line out to the 147 uses one G and ground then you only get half the signal hence low volume ,if both G's are used through a matching transformer then should have normal volume.

One G to ground has plenty enough signal to drive a 147, if everything is working right.

[alpine]

One G to ground has plenty enough signal to drive a 147, if everything is working right.

And if you want more, just use both GG terminals and put this in the line:
https://ssl.tonewheelgeneral.com/bui...no=122XB-INPUT