Re: 22H still humming and I have a 147 next to it that works fine. Somewhere along the way I have nothing connected to pin 5 on the hummer. I am in over my head here,people...HELP !!!
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I have a 1968 X77 that has a high pitch coming from the speaker. WHen I engage volume soft it diminishes 70% but is still slightly present. Has me totally baffled. Otherwise is sounds very good considering it's age.
On Thursday, June 8, 2023 at 12:17:12 PM EDT, Ali Asreco <aliasreco@...> wrote:
My Leslie hums too. But if the organ switch is on organ only there is no hum. So it's not the Leslie but the organ. It's a little old. 1969...? I can live with it...?
Ali
Le jeu. 8 juin 2023 ¨¤ 15:14, Wes Garland < wes@...> a ¨¦crit?: Oh - if the customer wants 147 switching everywhere........ just do that!
But remember that the front end of a 147 amp is unbalanced, and the front end of a 122 amp is balanced .... to do this properly so that you can just plug into a 147 organ, you need to change the front half of the circuit to match the 147, i.e. get rid of the dual triode buffer and go with the phase inverter .. you should be basically able to rip out of the front half of the amp and copy the 147 circuit. If you leave the feedback network post-6550 alone it will still sound like a 22H. Wes
Thank you Wes,The customer originally wanted all his gear interchangable,and all his other equipment is 147. I should have known better,shame on me ! But I will study and see if we can do it either your way or Chris' way but mostly I just want OUT ! On Wed, Jun 7, 2023 at 14:00, Wes Garland Alternatively, a Trek-II EIS relay ties in to the 6.3V lines, the audio lines, and the motor outlets... making it very easy to simply replace everything that affects switching but still stay working as a 22H.
Probably the best way to do this is to ditch the DC controlled
speed switching components in the 22H and effectively make it a
22W (if there ever was such a thing). You'll need a relay with a
mains voltage coil and change over contacts to replace the DC
relay. The normally closed contact will operate the fast motors,
and the normally open the slow motors. The relay coil will be
connected across pins 3 & 5 to match the wiring of the "W"
type or 147 Leslie series. Pins 1 & 6 are the signal pins with
pin 1 being ground, and pin 6 signal. Note that this is quite
different to the "H" or 122 wiring, where a balanced signal is fed
to pins 1 & 6 and ground is pin 2 (which you will be using for
the AC mains to the relay coil!). You might get it to work with
the original signal wire remaining connected to pins 1 & 6 and
an added ground wire to pin 1, or you may not. The original first
stage acts as a balanced signal amplifier, with positive signal
being fed to one half of the 12AU7 and negative to the other.
Looking at the schematic, it's possible that it may work
satisfactorily as a phase splitter,with one input connected to
signal ground, if it does, all well and good. If it doesn't, you
will need to look at the schematic of a 147, and rebuild the
circuitry around the 12AU7 to be the same as that used in a 147.
On 07/06/2023 15:52, john
alluneedtoknow via wrote:
I've had to put this project aside due to a large influx of other
work but where I last left it I disconnected everything and
started over and so now had audio and can't find the correct
wiring to get the speed switching to function. I've learned to ask
more questions before committing to something like this,and if I
ever get out of this one I will surely know better next time.?
--
Wesley W. Garland
Director, Product Development
PageMail, Inc.
+1 613 542 2787 x 102
--
Wesley W. Garland
Director, Product Development
PageMail, Inc.
+1 613 542 2787 x 102
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