Intercom and Radio Package

[Mark Julicher]

Tribe,

Here are some photos of the radio-intercom package we made for Doc. Start with the bare circuit board, wire it, mount it in a home-brew black box, and outfit the box with volt meter, aux power output, radio mount, input /output wires, circuit breakers, and a charging jack.

The large black umbilical has 6 wires. Namely, Master switch (2 wires) Strobe power (2 wires) and Push to Talk (2 wires). This large wire bundle is wrapped in "snake skin" and routed to the instrument panel via underneath the floorboards and up the side of the boot cowl. The Master Switch on the panel (Left toggle switch, not yet labeled) switches on the 12V 7AH gel cell mounted in the black box. The right switch on the panel operates a strobe light on the rudder. [We discovered a noise issue when running the strobe, so will have to shield this circuit somehow.]

Pilot and copilot PTT are routed to the yokes - see picture. The PTTs are grounded back to the box through the strobe ground wire - {maybe a source of noise?}

The box will be braced at the floor using angle brackets screwed to the wood and with a bungee cord holding it back to the kick plate.

Next post shows the installation.

[Mark Julicher]

Re: Intercom and Radio Package

Here is the panel, yoke, and installed package.

[Pearson]

Re: Intercom and Radio Package

I swear that looks just like the setup Broderick Crawford had in his car when he starred in "Highway Patrol".

[Mark Julicher]

Re: Intercom and Radio Package

Good One Richard! You are killing me!
At least we don't weigh as much as Broderick and we don't carry an itty bitty snub nose revolver.

I'll have to get DJ to build a more elegant radio box.

10-4

[Larry Lyons]

Re: Intercom and Radio Package

Where did the printed circuit board come from? Nice installation and if you went with LEDS for the nav. lights you would have a complete system.
Larry

PS: Careful how you answer, I see requests for copies in your future!

[Mark Julicher]

Re: Intercom and Radio Package

Larry,

The circuit board was developed by my oldest son (computer engineer in Maricopa Arizona) because he has a fab house that he does a lot of business with and he has the layout software. The silk screen still exists and more boards can be fabricated very easily. I would have to find out the cost but it will be cheaper for follow-on orders than the initial set up fee which was $125.

Design Parameters as Follows:

Built around the PS Engineering 1000 II intercom. Chosen for having dual squelches since none of my headsets match one another.

Handheld radio interface - because I had a handheld already and could not afford a Microair as per DJ's more elegant radio box.

Huge voltmeter - for weak eyes.

Aux Power output for my GPS.

Strobe output - for tail mounted Whelan strobe. unfortunately very noisy so I need to troubleshoot and shield this circuit

Circuit breakers - because I had a pile of them laying around and they are common as dirt in aircraft salvage.

Remote switches - because they are cool. They could have easily been mounted on the box itself.

Test button - to see battery voltage when the box is not with the plane. Would not be needed if master was not remotely mounted.

Remote PTTs - also cool, and could have been put on the box vs the yoke. These are a must have item and are not shown on my block diagram - but extremely simple to wire.

Block diagram is attached. The only modification I made was to eliminate the diodes. They really did not help.

[Pearson]

Re: Intercom and Radio Package

The thing I like most about it is that it eliminates the birds nest of wires and cables I have to deal with when I hook up my GPS, handheld com, and intercom. I think it is a great idea! Radio Envy!

[KewFlyer]

Re: Intercom and Radio Package

Mark:
Looks like a very nice set up, clean and practical.
Are you willing to make some for us? I'm sure there will be some take takers.
Ralph

[Larry Lyons]

Re: Intercom and Radio Package

Mark:
Looks like a very nice set up, clean and practical.
Are you willing to make some for us? I'm sure there will be some take takers.
Ralph

See; What did I tell ya?
If you decide to do this you can put me on your list of prospects. Larry

[VictorBravo]

Re: Intercom and Radio Package

That's a nice setup for using an existing handheld and an existing intercom. Also, be aware there are some really small radios now that have the intercom built in to the radio. That would simplify it even further.

My last T-craft used a Dittel gmbh German sailplane radio, which had the intercom built in. That radio is now obsolete and there are probably 2 1/4 round radios with intercoms, at a reasonable price.

The real gauge of the value of the device Mark built is whether it can be duplicated and sold at a significantly lower cost than a small built-in radio with the intercom already in it. If adding one of Mark's black boxes to your existing handheld radio comes in overall at half the cost of a new radio with integral intercom, then it's a huge winner.

[KewFlyer]

Re: Intercom and Radio Package

See; What did I tell ya?
If you decide to do this you can put me on your list of prospects. Larry

Well Larry.... if you add the cost of the intercom, the nav/com, battery, circuits, etc... all in a bundle...it a a winner all around.

I carry ( on trips..not all the time... way too much stress) the nav/com connected to the intercom ( floating all over the cabin), the wires to the motorcycle battery ( are they connected or not... is it charging or not, do I have plenty of juice until I get home to charge it), does the GPS have enough battery to take me home....is it charging ...wooohhh and still fly the plane safely and enjoy the flight.... uhm.

all simplified in one black box...priceless

That or getting a C-85-12 with full electric, starter etc... but it takes "all the old fun away"
Just my 2 cents [ not part of the Billion Subsidy package ]
Ralph

[Mark Julicher]

Re: Intercom and Radio Package

I would happy to supply circuit boards at cost.

However,

Building the whole unit is something I don't have time to do, and if I added up my time, this would be too expensive. Each installation will be a little different because handheld radios use different plugs, intercoms have different pin-outs, and I don't have a a steady supply of things like boxes, circuit breakers etc.

This is not a difficult project if you are patient. and yes, I LOVE that the rat's nest of wiring is GONE.

[Larry Lyons]

Re: Intercom and Radio Package

Mark I love the simplicity of this. As I will not be flying anytime soon there is no hurry, but this is one more thing I would love to stock pile for later. So yes I am interested in a board. Thanks, Larry

[guns68]

Re: Intercom and Radio Package

I would be interested in a board as well

[N74DV]

Re: Intercom and Radio Package

that looks great Mark. As you know we made one similar to that and place it in the same spot... in front of the seat in the middle. been using it for 2 years now and love it.

ours has voltmeter , PTT switch for copilot, MicroAir 760 radio, Sigtronics Intercom, aux input for iPod. All wired in stereo. We power it from a 2300mah 14.6 volt rechargeable lithium pack. We can get at least 3 hours of constant TX/RX in the pattern flight (towered airport) before recharging.