Two-Radio Headphone Switch
The
ability to listen to either one or both of two radios is easy to implement. It
requires only a switch (or switches), an assortment of connectors, shielded
audio cable and an enclosure. A simple way to do this is to visit the local
Radio Shack store with the following shopping list.
Parts List:
1 Stereo Audio Source Selector #42-2110 (*) $ 24.99
1 Stereo Y-Adapter (2 RCA plug #42-2471 $ 3.99
phono to one ¼” stereo jack)
1 Audio Cable Set (Four 3 ft cables #42-2309 $ 5.99
w/ RCA plugs @ end; color coded)
2 RCA/RCA Y-Adapter (2 RCA plugs to #42-2435 $ 5.98
single RCA jack)
2 Stereo Y-Adapter (2 RCA jacks to #42-2477 $ 5.98
single ¼” stereo plug)
TOTAL $ 46.93
(*)
Current Part No. 15-1956B
(Note:
Though some may think this a bit expensive, consider that there are over 30
connectors, 3 switches and 14 lengths of audio cable plus a “box” to prepare.)
[As this
was originally written some years ago, the Part Numbers and prices may have
changed.]
Stereo (1/4” plug & Jack)
Circuit 1 -
Tip
Circuit 2 -
Ring
Common - Shell
Radios
Right -
Radio 1 - Mult
Left - Radio 2 – Run
Headphone (Stereo)
Right
Speaker
Left
Speaker
Selector (2 RCA jacks @; Left and Right)
AUX 1 - Radio 2 (Left)
AUX 2 - Both Radios (1 @ headset
speaker)
AUX 3 - Radio 1 (Right)
1. Attach the Stereo (Jack) Y-Adapter to OUT.
(The RCA plugs can be swapped later to select L/R speaker)
2. Attach RCA/RCA Y-Adapter plugs to AUX 1 and
AUX 3.
3. Attach Stereo (Plug) to Headphone Input of
each Radio. (Mark the RCA jacks as to which goes to the Tip and which the
Ring.)
4. Connect Yellow RCA (Dual Plug) cable
from AUX 1 to Left Radio (preferably the Tip RCA jack).
5. Connect Green RCA (Dual Plug) cable
from AUX 3 to Right Radio (the Tip RCA jack).
6. Connect Black RCA (Dual Plug) cable
to AUX 2 Left jack. Connect the other end to the remaining RCA jack on the Left Radio, i.e. the Ring jack.
(Same adapter as the Yellow cable).
7. Connect Red RCA (Dual Plug) cable to
AUX 2 Right jack. Connect the other end to the remaining RCA jack on the Right Radio, i.e. the Ring jack.
(Same adapter as the Green cable).
1. AUX 1 switches Radio 2 (Left) to the Stereo
Headset, both speakers.
2. AUX 3 switches Radio 1 (Right) to the Stereo
Headset, both speakers.
3. AUX 2 switches Radio 2 (Left) to Left Stereo
Headset speaker and Radio 1 (Right) to Right Stereo Headset speaker.
I find
that the Audio Selector Box is large enough that I don’t have to chase it
around the operating table as I did with my “homebrew” dual-radio switch box.
Plus I can rest my left hand on it as I CQ on Radio 1 and tune for mults on
Radio 2.
1. Once the station layout is set, use tie-wraps
to tidy up the audio cables.
2. If you already have plenty of audio jumper
cables, you obviously don’t have to buy the package of “color coded” cable.
However they make tracing connection a lot easier. Four (4) more gray cables
running around the operating table can really add to the confusion!
3. Yes, I know a multi-pole toggle switch will
also do the job. But I like the “feel” of the push buttons, as I can sense by
feel which one I want without looking at the selector box. Plus they are easier
to manage with my large, clumsy hand.