The multi-transmitter diagram from the Volume 2 manual is below, Mark.  I don't think the control will work that way.  It is supposed to select one of four frequencies in a single VHF transmitter OR one (of two possible) HF transmitters that are then able to have their frequencies tweaked by the operator, just like always. 

At least that's the way I see it working.

- Mike  KC4TOS



On 10/26/2021 10:23 AM, MARK DORNEY wrote:
One thing I have noticed with the C-30 control. Only 1 button will remain pushed at any one time. If you press “2” , and then press “A”, the “2” button pops back up. I am thinking that the C-30 control is deaisigned to operate up to 6 transmitters, especially since the transmitters are not tunable by remote.  Transmitter frequencies were set and locked before flight unless the aircraft had a dedicated radio operator ( in which case both the transmitters and receivers would not use remotes ). 

“In matters of style, float with the current. In matters of Principle, stand like a rock. “.   -   Thomas Jefferson 

Sent from my iPhone

On Oct 25, 2021, at 10:35 PM, Michael Hanz <[email protected]> wrote:

 It can, and does control three transmitters when desired.  Page 50 in Volume 2 of AN 08-10-195, "Handbook of Maintenance Instructions for AN/ARC-5 Radio Equipment (VHF Components)" covers the operation and capabilities of this control box.  Its greatest drawback was simply the unreliability of the push button switches, which deficiency it shared with the SCR-522 VHF set control box.  Its replacement,  the C-30-A/ARC-5, reverted to the simple rotary switches used for other functions in the other control boxes and the problems went away.  Too bad they didn't have DeoxIT back then.  😁

- Mike  KC4TOS

On 10/25/2021 8:36 PM, MARK DORNEY via ARC5 wrote:
I also have a C-30/ARC-5 Control Box and am interested. Can this control box be used to control 3 Transmitters? 
Mark D. 
WW2RDO

On Oct 25, 2021, at 1:53 PM, dennis via ARC5 <[email protected]> wrote:
i have the C-30/ARC-5 control unit push button type i know abcd are channel select, lower button one is for off/on, the lower nos # 2&3 what are they used for  also can i use the control unit on a T-19 T22 TX if so is this control box wired the same as the C-29/arc-5 or different wiring  any type of help tnx dennis ka9dzr


-- 
Michael Hanz - KC4TOS