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Clearprop!
01-04-2021, 06:08 PM
Hello everyone!

I apologise for spamming this forum with questions but like previously mentioned im very interested in the cub.

How are Radio's handeled in a Cub without electrical systems? Can regular Radios be used? If so how would they be powered? Could I use, for example, a Battery used in a Glider?

Thanks in advance,

Tyler



Sent from my SM-G950F using SuperCub.Org mobile app (http://r.tapatalk.com/byo?rid=93960)

wireweinie
01-04-2021, 06:13 PM
Some use hand held radios and some use panel mounted radios with a removable battery. The battery is charged when needed.

Web

Dan Gervae
01-04-2021, 06:13 PM
Any rechargeable 12v battery will work....you can get quite a bit out of them....Even the battery on my old ICom handheld lasts many flight on a charge....I even have a little solar panel charger in my Non-electric Tcraft on floats.

Crash, Jr.
01-04-2021, 07:32 PM
I use a handheld in a RAM mount with a headset adapter wired up to a 2 place battery powered intercom and a PTT switch on the intercom. One 9v battery in the intercom to keep up with. I take the radio and GPS with me in my flight bag and charge them at home and put them back in when I go flying.

mvivion
01-04-2021, 08:05 PM
In my PA 11 with no electrical, I used a portable handheld radio, connected to a “take off” 121.5 ELT antenna, mounted in the fuel tank cover, for ground plane. I mounted a relatively small “power bank” battery on the floor to provide power to the radio. A push to talk switch mounted to the stick with Velcro. I mounted a sigtronics portable intercom to the left wing root, powered by a 9 volt battery.

This lash up would last a week or or more of regularly flying without recharge.

MTV

robertc
01-04-2021, 09:22 PM
Trig, TY91 in my PA11. The portable battery mounted on the floor gets me to Oshkosh and back to Idaho without recharging. I've been using the same battery for six years. The trig is easy to install, the head can fit in the panel and the radio is remote mounted. It weighs less than a pound and uses .2 amps per hour per hour.

bob turner
01-04-2021, 09:34 PM
I have a lot of experience with that. For right now, the best solution in a J3 is a Garmin GTR-200, mounted in the wing just ahead of the rear spar, and driven by two 7 ah batteries in series. Use the internal intercom.

I have an SL-40 in my personal Cub. It is a better radio, and works on one battery (12 volts) but it’s memory channels are simply horrible. HORRIBLE!

The J4 had a Becker. They are great radios when they work, but when they quit, it costs half the price of a GTR-200 to fix it. It quit for the last time two weeks ago, and I will probably sell it to Web. I bet the internal fuse took a dump.

Portables - using an Icom A-6 in the J4, hooked to the ship’s antenna. So far no complaints from the tower.

We used an A-21 for a while, and everybody but the tower could hear us crystal-clear. That’s why we got the GTR-200.

Two cautions - well, three:

One - the Icom radios have accessories that do not interchange. You cannot use the headset adapter for an A-6 on an A-21 or an A-25, and likewise. Their engineers make minor changes to power and headset plug-ins for each model.

Two - the GTR-200 is a 12 volt radio. We get 45 minutes out of a fully charged 7ah 12 volt battery, and twelve hours out of two of them in series.

Three - the GTR has inadequate squelch range. We are seriously bothered at MYF bySoCal bleed-through on 125.7. No other radio has that problem. Garmin doesn’t care. It is still the best radio for a J3.

We use it in the Stearman, too - open mike intercom. Spectacular! (Except for the RF interference)

JP
01-04-2021, 09:48 PM
I have my Aera 510, Icom A5 and intercom running off a very small 12v 5 amp hour duracell battery. I recently purchased a NOCO 400 jump battery that is a very light weight, compact li po with 1000 amps that I might give a go for day trips. It weighs a tenth of the duracell. It starts boats, cars, etc. with ease. Be interesting to see how long it will run the flight deck....

wireweinie
01-04-2021, 11:45 PM
Bob

I tried to get you to sell me that Becker last time you had trouble. Still waiting to buy it.

You sure you're using two twelve volt batteries in series? That would give you twenty four volts.

Web

bob turner
01-04-2021, 11:59 PM
Yes. The 12 volt battery would sag to 11 1/2 volts in short order. We found it safer to hook the spare battery in series, then change out both in ten tach hours. The combo can sag all the way down to 20 volts and we are still transmitting.

Happily, the Garmin receives long after the transmitter stops, so if we ever forget, we can wiggle our wings.

The other Becker was in the Stearman. Believe it or not, they e-Bayed it after they had it fixed. That was a loser.
This one has a complete wiring harness hooked (by power and ground) to a Becker transponder and encoder. Those were working, but I yanked them out before my partner got a chance to educate the controllers as to our equipment.

I have seen some nasty wiring jobs, but never one like this! Miles of spaghetti, no color coding except in the Becker harnesses, and clotheslined around the fuel tank, only to wind up in inaccessible loops under cable ties. The aircraft is otherwise beautiful!

wireweinie
01-05-2021, 02:00 AM
No one color codes wire harnesses in aircraft.

Let me know when you want to sell the Becker.

Web

Waldo M
01-05-2021, 08:52 AM
Clearprop, all the responding posts are good insights. I use the same set-up in a PA-11 with no electrical system that Crash Jr. does.

I bent up a sheet metal mount for the hand-held radio and placed it just ahead of the throttle knob. That eliminates the need for a push to talk switch mounted on the stick and the associated cord that tends to get in the way. With my left hand on the throttle, I can use my index finger to activate the PTT switch on the radio itself to transmit. I velcroed the portable intercom to the "shelf" between the throttles. That is a workable location that allows the headset jacks to be easily reached from either seat.

One thing that should be recognized from the discussion is that you really need an external antenna for any transmitting range. I use an AAE dipole antenna mounted inside the fuselage behind the baggage compartment and ran a coax cable from the antenna and behind the sheet metal interior piece to exit near the radio mount. The dipole antenna does not need a ground plane. If you restore a Cub to original configuration, there will not be an antenna appearing on the outside of the airplane.

Crash, Jr.
01-05-2021, 11:25 AM
One thing that should be recognized from the discussion is that you really need an external antenna for any transmitting range.

100%. I forgot to mention I have an external antenna mounted on top of the wing root fairing. Very much needed for any usable range. Surprisingly the little Icom with antenna gets around 15-20 miles range. Not too shabby.

The external battery thing is intriguing. The internal rechargeable batteries on the Garmin 396 and Icom last around 4-6 hours of continuous use so something extra is needed for long trips.

bob turner
01-05-2021, 11:41 AM
I color code, and use shielded twisted pairs. I don't do it professionally, so need to keep track of which wire is signal and which is return inside the shield.

The Becker harness has color codes - red for power, black for ground, yellow for something, etc - but they all just hooked into this giant bundle of white. The PTTs will be the most difficult to trace; they came in to the system at the mic jacks. It would be easy if I were two feet tall with tiny hands and flashlights on my glasses. I did label stuff, but rarely trust someone else's wiring. One butt connector had six wires on one side.

bob turner
01-05-2021, 11:44 AM
By the way, we used the same 7 AH gel cells to power the portable Icom. Lasted a very long time. Icom engineers vary the input voltage, so you have to buy a different battery adapter for each model.

supercub1999
01-05-2021, 08:21 PM
A freind uses this small 5" tall 4" wide 3" deep AGM battery https://www.amazon.com/gp/product/B00VRDONM0/

Puts it on a 1 amp charger for a day after flying.

JP
01-05-2021, 08:31 PM
Yes on external antenna. My experience with handhelds is that they have deadspots in the broadcast and really don't go far in any event. My garmin with a wing antenna can be heard for quite a distance.

cubflier
01-05-2021, 10:10 PM
JP - I'm interested in how the NOCO holds up as far as capacity is concerned. I assume it's a GB40? I inherited a GB50 that I'm playing around with it to see how it holds up to my favorite Antigravity packs that a smart friend caused me to buy.

Jerry

RVBottomly
01-06-2021, 10:32 AM
I use an AAE dipole antenna mounted inside the fuselage behind the baggage compartment and ran a coax cable from the antenna and behind the sheet metal interior piece to exit near the radio mount. The dipole antenna does not need a ground plane. If you restore a Cub to original configuration, there will not be an antenna appearing on the outside of the airplane.

Thanks for that. I hadn't heard of AAE dipole antennas. Interesting.

http://www.advancedaircraft.com/