How to make it work....

T Bone

T Bone

Pre-takeoff checklist
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T Bone
Okay, I rent a wide variety of airplanes (there are 6 152's in the fleet I rent from for example). Varrying degrees of avionics. Some of the planes do not even have a second com.

I do carry an Icom A23 Nav/Com as a backup, but I actually bought it with more in mind. I know they are quite limited in tx, but it seems to receive pretty well. What I was wondering, seems like there's gotta be a way to rig this into the main com/intercom system and use as a defacto com II (at least to pick up ATIS, or monitor approach before it's time to contact). I was thinking maybe through a portable intercom? (BTW, I plan to get a portable intercom with stereo inputs for music, and a cell phone interface). Seems like all I'd need are a couple of adapters (male plugs both ends) to go from the headset adapter to the intercom. Haven't found these as yet. Anyone know of a source? Anyone know if this will even work? Or is there a better way?

Thanks in advance for the input.
 
T Bone said:
Okay, I rent a wide variety of airplanes (there are 6 152's in the fleet I rent from for example). Varrying degrees of avionics. Some of the planes do not even have a second com.

I do carry an Icom A23 Nav/Com as a backup, but I actually bought it with more in mind. I know they are quite limited in tx, but it seems to receive pretty well. What I was wondering, seems like there's gotta be a way to rig this into the main com/intercom system and use as a defacto com II (at least to pick up ATIS, or monitor approach before it's time to contact). I was thinking maybe through a portable intercom? (BTW, I plan to get a portable intercom with stereo inputs for music, and a cell phone interface). Seems like all I'd need are a couple of adapters (male plugs both ends) to go from the headset adapter to the intercom. Haven't found these as yet. Anyone know of a source? Anyone know if this will even work? Or is there a better way?

Thanks in advance for the input.
Click to expand...

Mic and headset plugs are (or at least were) readily available at Pacific Coast Avionics.

It's been a very rough dangerous day here so I refuse to think right now but make absolutely sure you know what you're doing before you go building strange adaptors and plugging things into each other lest you let the smoke out of something gawd awful expensive.
 
Thats a really good question. We have the A5 with the headset adapter but I'm not sure how it would work plugged into the intercom. I think it might work with the male/male splice however I think the transmissions would be open mic meaning that anyone that was talking in the plane during the transmission would be "on the air".
 
T Bone said:
Okay, I rent a wide variety of airplanes (there are 6 152's in the fleet I rent from for example). Varrying degrees of avionics. Some of the planes do not even have a second com.

I do carry an Icom A23 Nav/Com as a backup, but I actually bought it with more in mind. I know they are quite limited in tx, but it seems to receive pretty well. What I was wondering, seems like there's gotta be a way to rig this into the main com/intercom system and use as a defacto com II (at least to pick up ATIS, or monitor approach before it's time to contact). I was thinking maybe through a portable intercom? (BTW, I plan to get a portable intercom with stereo inputs for music, and a cell phone interface). Seems like all I'd need are a couple of adapters (male plugs both ends) to go from the headset adapter to the intercom. Haven't found these as yet. Anyone know of a source? Anyone know if this will even work? Or is there a better way?

Thanks in advance for the input.
Click to expand...

It could be done but it will take more than a "couple of adapters". The headphone output of the radio needs to be coupled into the copilot's mic jack but the respective signals are not directly compatible. The mic input has DC on it (mike bias) which could harm the portable radio and the radio's output is possibly the wrong signal level.

Another option would be to use an intercom that has a music input and connect the headphone output of the handheld to that. All you would need then is a cable with the appropriate plugs and you might find that at Radio Shack.
 
Back oveer on that other board, a couple of guys ran a test using handhelds vs installed. If I recall, they did fairly well with just the handheld talking to ATC. Maybe someone has the details.
 
silver-eagle said:
Back oveer on that other board, a couple of guys ran a test using handhelds vs installed. If I recall, they did fairly well with just the handheld talking to ATC. Maybe someone has the details.
Click to expand...
I believe it was Ed Guthrie who did that. Almost made a believer out of me, a chronic handheld transceiver skeptic.
 
silver-eagle said:
Back oveer on that other board, a couple of guys ran a test using handhelds vs installed. If I recall, they did fairly well with just the handheld talking to ATC. Maybe someone has the details.
Click to expand...

The couple of guys was Eamon and I, and, as luck would have it, I'm a packrat and I still have the handwritten notes from our test.

The test was done while flying from New Garden (N57) to Smith Mountain Lake IFR in Eamon's C182. The test plan was that I would listen/talk via the ICOM A23, and Eamon would listen/talk via the aircraft COM. When ATC handed Eamon a frequency change he would acknowledge via the aircraft COM and I would make the initial contact on the new frequency via the handheld. The totally unscientific basis for the test was that the change points were randomly selected by ATC, and that the change points were probably the worst transmission/reception points along the route (that last bit totally unverified supposition). The other test factor was that we filed for and/or requested the MEA or lowest altitude for the route so as to make reception/transmission under the most challenging conditions for the airway/route. I kept a record of the contact point relative to an airway route, the nearest VOR, and DME from that VOR according to the aircraft equipment, as well as the aircraft altitude. When ever possible I also queried each controller as to transmission quality.

The results:

V29 4 nm N of ENO @ 4000', Dover approach 132.42. "Scratchy but readable."

V16 24 nm S of ENO @ 4000', Patuxent approach 124.55. No contact after two attempts at which point Eamon took over on the aircraft COM. The controller was very, very busy. Eamon tried 3 times before he got a reply. IOW, unknown.

V16 32 nm N of PXT @ 4000', Patuxent approach 120.05. "Excellent."

Flat Rock VOR, 060 radial, 30 nm, 4000', Potomac approach. "Good."

Eamon canceled IFR at this point so I opted to make one more test. The A23 will duplex (receive VOR voice while transmitting on COM frequency), so I tried a duplex contact with Leesburg Radio via the Flat Rock VOR (122.1T/113.3R) at ~2000-1400' (Eamon was doing a dive bomber imitation at that point), 20 nm out on the 030 radial. During this duplex test I received an updated weather for Lynchburg and passed a PIREP to FSS.

Throughout the test I used the A23's "rubber ducky" antenna and the ICOM headset adapter with PTT switch. I positioned the antenna so that it was vertical or near vertical above the glareshield within the front windscreen area.
 
I have added another antenna to my aircraft just for emergency use for my handheld. Prior to IFR flights I will set up the adapters for headset, press to talk and wire attachment for the antenna. If needed than all I have to do is connect into antenna plug and connect my headset up. Done deal. I have found that handhelds do not do very well without this external antenna. Also for a back up system I have a pilot III gps that is mounted on the dash. It is hardwired in so it gets it electrical power from the aircraft. In event of electrical failure then its internal battery's take over. So this gives me a back up gps system and comm system.
 
Okay, thanks again for the replies (and thanks Ed for the test results! Adding a bit more confidence to my handheld....).

Now, in order to simplify this, I have another thought. This would use the headset adapter that came with the radio. I'd need to get a "Y" cord made up. Female jacks to plug my headset into, then Y to 2 males, one going to the headset adapter and one to the ships com. (or portable intercom). This would isolate the handheld as com 2 to the pilot only, but would it in fact work? Or would splitting the cable in such a manner degrade the signal to/from either?

Thanks again for replies.
 
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