26-1 box AC wire connection- A-100, Leslie 145

[gude2000]

I have the 26-1 box to connect my A-100 to a Leslie 145. I got the black, green and red wires figured out; however, I don't know exactly where to connect the blue and gray AC wires. I am not sure what "switched AC mains" means...Where is that? On the AO-39? Do you connect these to the GY and BL tabs there? Do the wires connect to the AO-28 pre-amp (as Captain Foldback's interactions suggest- but I don't know exactly where....), or to the AO-39??

Can anyone tell me EXACTLY where to solder the blue and gray wires? If you can include a picture, it would greatly help!!!

Thanks!

[ShadyJoe]

I can't tell you exactly where. "Mains" means the main AC power source from your home, the outlet. You use a switch to turn on the organ. The main AC wiring after the switch is the switched AC mains.

[gude2000]

So I see some blue and gray wires coming out of the on-off switch box going to a small metallic box on the preamp; they are soldered to tabs 3 and 4 on the upside down AO-28). Can I solder the blue and gray wires from the 26-1 box to tabs 3 and 4 with the corresponding colors? My blue and gray wires are too short to reach the on-off switch area...
Thanks!

Update: I did this and it works, except that when I switch to "Main" on the half-moon switch, a loud hum comes out of the Leslie. The other 2 positions work fine and do what they are supposed to do with no noise. I got the AO-39 hooked up right (black of the 26-1 to the ground tab (2nd tab), green wire out of tab 1 cut and spliced to the red wire of the 26-1, and green wire from the 26-1 spliced to the other end of the cut AO-39 green wire going to the organ speaker). I wonder if this has anything to do with the way the half-moon "tremolo" and "echo" switch cables go into the 26-1 box? Does it matter how these (or the 6-pin cable into the leslie for that matter) are connected, as long as they fit well? If not, why the loud hum on the "main" position?

Thanks for your help. I am a complete noob going way beyond what I normally do...

[geoelectro]

When you connect a 145 it normally connects to the speaker output of the organ. When switching to the Leslie only, the load is provided with the load switch in the Leslie. If you have to load switch set to open, when you switch the Leslie off, you will have hum. If you connected to the preamp, the load switch would need to be off or you won't get much volume from the Leslie. However, you're back to having hum when the Leslie is switched off. This is because the 26-1 simply breaks the circuit to the Leslie leaving the input to the Leslie floating and not terminated. I have added a 330 ohm or 470 ohm resister across the Leslie input to reduce this problem. Those values won't have much effect on volume but enough to terminate the open input.

Did you connect the 26-1 kit to the speakers in the organ or the preamp?

Geo

[gude2000]

Thanks, Geo.

I just connected the AC wires (blue and gray) to the corresponding tabs on the pre-amp. I put the rest of the 26-1 wires (black, red and green) in between the AO-39 amp and the right speaker on the A-100 cabinet (see my prior post for specific connections).

I'm sure someone has connected the A-100 to a leslie 145/147 with a 26-1 box before... Is this hum on the "main" position normal, and therefore, another resistor has to be added to the circuit, or is there something more basic going on? Again, I think my connections are correct, so I'm not sure what the problem is...

Any other ideas?

[Wes]

Now that you mention it, I had this issue with the 26-1 kit in my L122, modified slightly to connect to a 51C. Next time I hook up a 26-1 kit I will be using George's trick. Geo, how big a resistor? I guess with that much resistance even 1/2W would be okay?

Wes

[jdoc]

did you mod the kit or the Leslie amp, as you know I am a little behind in my 51 Project?

[geoelectro]

Now that you mention it, I had this issue with the 26-1 kit in my L122, modified slightly to connect to a 51C. Next time I hook up a 26-1 kit I will be using George's trick. Geo, how big a resistor? I guess with that much resistance even 1/2W would be okay?

Wes

Again, this mod is when connecting to the preamp which is why you can't use the load switch in the Leslie. I use a 1/2 watt resistor n that case.

Geo

[Wes]

Joe -- I converted the kit, very easy job. You also need to provide a load on the organ side as the 51 does not have a load resistor socket.

PO in my case had already supplied the load resistor which is a bit odd for a type 47 hookup!

[gude2000]

As I said, I'm connecting the non-AC 26-1 wires to the AO-39 power amp and the organ speaker (as it is supposed to be and this link corroborates: http://www.captain-foldback.com/Leslie_sub/tips5.htm ). So all this stuff about the preamp and resistors does not help me... Sorry.
Can someone who has installed this box help me solve the hum issue on the "main" position? Has nobody in this forum connected an A-100 to a leslie 145/147???

[geoelectro]

As I said, I'm connecting the non-AC 26-1 wires to the AO-39 power amp and the organ speaker (as it is supposed to be and this link corroborates: http://www.captain-foldback.com/Leslie_sub/tips5.htm ). So all this stuff about the preamp and resistors does not help me... Sorry.
Can someone who has installed this box help me solve the hum issue on the "main" position? Has nobody in this forum connected an A-100 to a leslie 145/147???

Did you locate the load switch in the Leslie amp? Next to the volume control. Set it to 8 or 16 ohms. If that switch is working, that's your hum fix.

Geo

[gude2000]

Thanks Geo!!!

Got the problem fixed!. All I had to do was increase from 8 to 16 ohms on the leslie 147!!! (I have a 145 shorty with a 147 amp...).Crazy, because the 26-1 box printed instructions specifically say to set it to 8 ohms... It all works flawlessly now!

Thank you!!!

[geoelectro]

Either position would have fixed the hum. I suspect the 8 ohm position is not working, or is open. A bad switch, connection or resistor. Glad it's working!

Geo