Radio Box

[TimHicks]

I'm planning to make a box to hold a 5Watt radio and intercom.
Similar to what several other members have done.

The big rectangular component with a round face is a MicroAir M760 radio.
The rectangular-faced component below that is the intercom (probably PS Engineering PM1200)
The round-faced component with a round body is a voltmeter. But the one I planned to put in there is no longer available. So the actual one probably won't look like this.
The two rectangular components completely inside the box are 2.3 Ah batteries.
Two circuit breakers are peeking out of the pilot side of the box.


Missing from the sketches below are several ports in the box. I'll have two charge ports probably on the co-pilot side. One is a cigarette-lighter jack.
Also a music input. And the antenna connection comes out the pilot side near the circuit breakers.

I'm interested in any feedback. Anything look like it won't fit / work?

I imagiine that it is a fairly self-contained unit that I can remove from the airplane for battery charging.
I imagine strapping it to the kickplate below the front of the seat. But I don't have a concrete plan for how to make a strap, yet.

[Hank Jarrett]

Re: Radio Box

When you actually make it try and stack components to make it as flat to the kick plate as you can. I built mine to go into an original pre-war size battery box and once in a while I bump a shin against the box. A half inch further back and I would always miss it.
If you are always going to take it out to charge it you could put the charge plug on the aft side where it would be covered by the kick plate when in use and leave useful face space.
You also want to dummy up a box and put all the connections into it before you freeze the design. The wires and jacks for the headsets got moved a few times on mine before I was happy. Also don't forget you will need two PTT jacks somewhere and a switch so you can isolate the passenger to intercom only so they don't start chatting to you and it goes out on the radio. I ran the radio connections from the pilots "A" pillar where the radio clips through the pilots under door cover and behind the kick plate to a hole right at the battery box. There were a LOT of zip-ties to make sure nothing got in the way of the gear. I wanted a volt meter and an amp meter, but haven't found any of a decent size (small enough to fit in but big enough to read).
The original batteries before the war were held to the floor by two bolts through tangs on the box, but since mine will be charged in place I plan to add a fastener through the case so it can be tied to the steel tube behind the kick too. Mine is also designed to connect to a wind generator so I have a field, master and accessory switches as well as fuses and several hidden 12V Cigar jacks for hand held devices. Of course all of this is put in with FAA Velcro and zip ties. ;-) I was lucky that the original design hold down bolts were on an old floor board I measured so I could put the box in the original position. Funny thing is the box isn't even in the plane right now since I really don't use it yet. It's all in one of the boxes in the hangar.
Hank

[Mark Julicher]

Re: Radio Box

Is there any reason you are not going to use the built in intercom in the Microair radio?

[astjp2]

Re: Radio Box

Its a piece of shit!

Is there any reason you are not going to use the built in intercom in the Microair radio?

[Mark Julicher]

Re: Radio Box

Its a piece of shit!

No need to hold back your feelings! But That's good enough reason for me.

[astjp2]

Re: Radio Box

Well its not VOX, most people that have them do not understand you need a PTT for the intercom only, they change squelch with altitude, good for a back up only. It really sucks if you dont have shielded ignition, there is a nice buzz there all of the time. I had it for years, I went with a PS1000, best thing I did, could play music on long trips by myself. It was hard to stay awake when you have a 3-4 hour nonstop flight. Flights across Alaska or Wyoming are just long. Tim

[TimHicks]

Re: Radio Box

Mark and Tim,
I know that you have both built similar packages. I value your feedback.
I'm not completely sold on the MicroAir. Mark, I think that you used the Flightline FL760. Do you use the internal intercom on that radio?
Any feedback on the performance/quality/robustness of the FlightLine?
I know also of the XCOM radio that fits in the same envelope. Does anyone know how it compares with the MicroAir and the Flightline?

I also want the ability to turn off the radio and leave the intercom on. And to be able to run the intercom from one battery and the radio from the other.

Hank, my current design (seen above) uses a cabinet that is 5" deep (that's how far it juts out forward from the kickplate). How deep was yours?
I had only planned on installing one PTT jack. I'm not sure that I have ever had a need for my co-pilot to have his own PTT.

[Hank Jarrett]

Re: Radio Box

The pre-war boxes were approximately 4.5 x 4.25 x 7.5 with the box sticking forward of the kick plate by 4.25.
These are NOT accurate dimensions, just something taken with a cheap ruler on the run. I do have the pattern to make them.
I have posted photos of the box before but they are not stored on the computer I am using right now.
Hank

[otrcman]

Re: Radio Box

I'm not completely sold on the MicroAir.

Tim, Please excuse me for editing your quote here, but I wanted to reply to just one thing.

I also have wondered about the MicroAir for a project I'm working on. A while back I stopped in at Chief Aircraft in Oregon to buy some miscellaneous items. While there I spoke to their avionics guy and asked them why they offered the Becker radios but not MicroAir. He said they had carried the MicroAir at one time but had so many returns for service that the gave up on them. I asked about the Becker and he said it seemed to be bulletproof.

That's just one more data point into the hopper, but it was a significant one for me.

Dick

[N74DV]

Re: Radio Box

Your design is very similar to what we did. Works great. We just velcroed it to the plywood floor board right in front of the seat. We used the Microair and we get a good 8-12 miles range no problem. You can see details here:

http://vb.taylorcraft.org/showthread.php?3955-Comm-Radio-Box

[Mark Julicher]

Re: Radio Box

Quote "Mark, I think that you used the Flightline FL760. Do you use the internal intercom on that radio?
Any feedback on the performance/quality/robustness of the FlightLine?"
________________________

Well, the Flightline intercom is rather poor too. The biggest problem is that it has ONLY a three setting, software squelch and that is insufficient for certain headsets. Second problem is that there is no volume for the intercom, so the only way to adjust intercom volume is by using the headset's volume control. My headset will not turn the volume down far enough to keep the intercom from being too loud. I have a new PS engineering intercom on the shelf, and I may just haul off and install it in my radio box.

I would love to hear more about the Becker radio.

[otrcman]

Re: Radio Box

I would love to hear more about the Becker radio.

Me too ! The story I related regarding Chief Aircraft would seem to indicate that they thought Beckers were superior to the MicroAir. But then they were selling the Becker, so their preference might have carried some bias. I've never actually met anyone who owned a Becker. Maybe because they cost a bit more.

Dick

[TimHicks]

Re: Radio Box

I just noticed that, on the PS-Engineering website, all of their intercoms say their input voltage is 13.8 - 27.5 Volts DC. I was hoping to use this with 12V batteries. Am I missing something?

[N-43121]

Re: Radio Box

Me too ! The story I related regarding Chief Aircraft would seem to indicate that they thought Beckers were superior to the MicroAir. But then they were selling the Becker, so their preference might have carried some bias. I've never actually met anyone who owned a Becker. Maybe because they cost a bit more.

Dick

I have a Becker and it is great. A couple friends have them in their supercubs and have been very happy too.
Rod

[astjp2]

Re: Radio Box

12v battery will be fine, that is what I use. Tim

I just noticed that, on the PS-Engineering website, all of their intercoms say their input voltage is 13.8 - 27.5 Volts DC. I was hoping to use this with 12V batteries. Am I missing something?