Push to talk switch fabrication.

S

skypilot180

Filing Flight Plan
Joined
Feb 3, 2013
Messages
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Display name:
Jeff D.
Hello one and all.

I am new to this forum and I am looking for information
on a material list to fabricate a PTT switch assembly
for a Icom A-22 hand held. I have the headset adapter, but I need to make a PTT for a top of stick
mount. Purchased a over the counter unit, disassembled
and has four wire contact at the switch and what I am assuming a 1/8 inch jack plug.

Thank you.

Jeff.

 
skypilot180 said:
Hello one and all.

I am new to this forum and I am looking for information
on a material list to fabricate a PTT switch assembly
for a Icom A-22 hand held. I have the headset adapter, but I need to make a PTT for a top of stick
mount. Purchased a over the counter unit, disassembled
and has four wire contact at the switch and what I am assuming a 1/8 inch jack plug.

Thank you.

Jeff.

Click to expand...

You can buy them pretty inexpensively at Sporty's or other such online shops. I think you will have some trouble sourcing the parts and probably won't save any money.

Edit: just noticed you said you had purchased an over the counter unit. Can you disassemble and use the parts? The mic plug is not a standard size.
 
Last edited:
skypilot180 said:
Hello one and all.

I am new to this forum and I am looking for information
on a material list to fabricate a PTT switch assembly
for a Icom A-22 hand held. I have the headset adapter, but I need to make a PTT for a top of stick
mount. Purchased a over the counter unit, disassembled
and has four wire contact at the switch and what I am assuming a 1/8 inch jack plug.

Thank you.

Jeff.
Click to expand...

Welcome to POA.....:thumbsup::cheers:
 
John,

Cant use anything from the over the counter unit. Want to mount switch in stick and cable is to short to reach the radio. Its mounted over head.

Jeff
 
Aircraft Spruce sells the cable I need but am unsure if the stick mount
PTT swith the sell is uded with a four wire set up and I am clueless as
to the plug I would need.

Jeff:confused:
 
The mic is a .206" plug. They might have it at Spruce. I am sure that is your best bet. The headset is a standard 1/4".
 
Here is another post describing PTT

iGismo
(User ID: gismo)
Touchdown! Greaser!
PoA Test Pilot



Join Date: Feb 2005
Location: Minneapolis
Posts: 10,886
Re: Intercom or radio transmit issue
Quote:
Originally Posted by pericynthion
The push to talk is really just a binary thing - on or off - so if the radio is transmitting at all then I'd be surprised if replacing the PTT fixed your problem. Have you flown again since? And how are things over at the old T's?
Virtually all aftermarket (i.e. "portable") PTTs have two N.O. contact sets. One set connects the microphone to the mic audio line and the other shorts the Key (transmit on) to ground. The microphone to audio line carries voltage to the microphone's internal amp as well as the audio back to the radio or intercom. If the Key contact works the radio will go into transmit mode and if the mic contacts are corroded the mic audio will be missing or very attenuated. A poor contact on the key line can also cause problems if the radio's key input isn't designed to handle a high resistance (many are not).
__________________
-lance B55, CP65
Click to expand...
 
John,

Just mic'd pin diameter. .125. Plugs into the splitter on the headset adapter. Gottt be some way to get the parts to do the job.

Jeff.
 
skypilot180 said:
I am new to this forum and I am looking for informationon a material list to fabricate a PTT switch assemblyfor a Icom A-22 hand held. I have the headset adapter, but I need to make a PTT for a top of stickmount. Purchased a over the counter unit, disassembledand has four wire contact at the switch and what I am assuming a 1/8 inch jack plug.
Click to expand...
Here's a schematic from where I converted an Icom handheld to a panel-mount radio:
rad_plug.jpg

This is for an Icom IC-A5, but I suspect it's similar to your radio. Check out the connections in the adaptor with an ohmmeter. You can leave off the Potentiometer off, just run the wire directly from the tip of the plug on the adaptor to the microphone jack.

Ron Wanttaja
 
John,

There is no listing for the plug used on my PPT switch. Bummer.
I will find the info some place. As I stated, Spruce sell cable and switch. Have to find the correct pin and source.

Jeff. :rolleyes2:
 
Some switches have 4 pins to make it easier to solder into a PCB even though two of the pins are redundant. All you likely need is a single pole, single throw.

Mouser.com has more switches than you can shake a stick at. A "Tactile" switch that has a definite click feel is nice.
 
Geoff,
I am 100 miles north fo you. Saginaw.

Small world.
 
skypilot180 said:
John,

There is no listing for the plug used on my PPT switch. Bummer.
I will find the info some place. As I stated, Spruce sell cable and switch. Have to find the correct pin and source.

Jeff. :rolleyes2:
Click to expand...

Unless it is a helicopter model or powered, all aviation headsets have the same size jacks (I guess airline might be different, too). I don't understand why yours would be different. This is an airplane, right?
 
John,

Regular GA style headset. Sigtronics. Purchased the radio adapter
and PTT from www.mypilotstore.com Everything was for ICOM A-22
radio. The headset adapter has regular GA style jack plugs except
to the PTT jack. It has 1/8" jack.

Jeff.:confused:
 
You guys are not allowed to fabricate or make stuff for your airplanes....!!
You need to purchase parts that are TSO or PMA, period.

How many times we need to talk about this issue?
:nonod:
 
WarriorPilot said:
You guys are not allowed to fabricate or make stuff for your airplanes....!!
You need to purchase parts that are TSO or PMA, period.

How many times we need to talk about this issue?
:nonod:
Click to expand...

Here is a picture of the radiator mount I fabricated that is right in front of the exhaust system I fabricated.
GEDC0819.JPG
 
you can get everything you need from Aircraft Spruce, or you can get everything you need, pre-wired, to plug and play from Stein Air.

All it takes is some 2 conductor wire, a momentary push button switch, a piggyback mic plug, and a soldering iron. If your plan is to hardwire it into the system, you don't need the piggyback.
 
Warrior Pilot,

I fall into EAB catogory. So much for TSO /PMA.

Jeff.
 
WarriorPilot said:
You guys are not allowed to fabricate or make stuff for your airplanes....!!
You need to purchase parts that are TSO or PMA, period.

How many times we need to talk about this issue?
:nonod:
Click to expand...
Here's a picture of my wooden transponder. No PMA here! :)
elect_maple2.jpg


Ron Wanttaja
 
WarriorPilot said:
You guys are not allowed to fabricate or make stuff for your airplanes....!!
You need to purchase parts that are TSO or PMA, period.

How many times we need to talk about this issue?
:nonod:
Click to expand...

Go buy a portable PTT assembly at the pilot shop and see if you can find any TSO or PMA identification on it. You won't on most, same as you won't find anything on most headsets.

Dan
 
Many of the Icom handhelds don't use the mike-tip-grounding thing to activate transmit. They just connect the mic into the circuit. Mine uses a common pushbutton switch that fires a relay that makes the connection between the mic and the ring on the mike plug in the radio. The relay switches my mike between the radio and intercom. Simple as dirt.

Dan
 
Dan Thomas said:
Go buy a portable PTT assembly at the pilot shop and see if you can find any TSO or PMA identification on it. You won't on most, same as you won't find anything on most headsets.

Dan
Click to expand...
Headsets from Telex and Dave Clark are PMA, not sure where are you buying yours. If you go to WalMart or Radio Shack probably you won't find anything TSOd or PMA. That is up to you folks.
As the FAA says: "responsibility of the installer"
:yikes:
 
WarriorPilot said:
Not sure what airplane is that. Looks like a Piper Cub.
:yikes:
Click to expand...
I don't recall ever seeing a water cooled Cub.

But in any case, it's not going to be a major alteration if my fabricated parts are replacements for the original home-builder fabricated parts. (FAR 21.93)

When I plug 2/3 of the holes in the cowl and re-locate the radiator, that is a major alteration and then I will follow the directions in the operating limitations for major alterations. Mine say that I need to contact the FAA and recieve a response in writing before flying after the alteration. But others are different.

http://www.eaa.org/experimenter/articles/2011-02_darside.asp

See also: http://www.faa.gov/regulations_poli....cfm/go/document.information/documentID/99860 which applies to type certificated aircraft.
 
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WarriorPilot said:
Not sure what airplane is that. Looks like a Piper Cub.
:yikes:
Click to expand...

I'm pretty sure you are just being a smartie for our entertainment, but just in case you are that uneducated: An owner of a Piper Cub can legally make his or her own parts if necessary. My Luscombe has several owner made parts.

How in the world do you think our antique classic birds keep flying? Magic?

Deb
 
FELLAS,

Thank you for the input on the PTT switch. I ended up puchasing a jack pin
and momentary switch from Radio Shack. I used 18 guage tefzel for leads.
Worked like a charm.

I still cant figure why the over the counter unit had a four wire contact on
the switch. They were bundled two per side on the jack pin.

Jeff.
 
skypilot180 said:
FELLAS,

Thank you for the input on the PTT switch. I ended up puchasing a jack pin
and momentary switch from Radio Shack. I used 18 guage tefzel for leads.
Worked like a charm.

I still cant figure why the over the counter unit had a four wire contact on
the switch. They were bundled two per side on the jack pin.

Jeff.
Click to expand...

Single switch for both pilot and co-pilot mic?
 
skypilot180 said:
FELLAS,

Thank you for the input on the PTT switch. I ended up puchasing a jack pin
and momentary switch from Radio Shack. I used 18 guage tefzel for leads.
Worked like a charm.

I still cant figure why the over the counter unit had a four wire contact on
the switch. They were bundled two per side on the jack pin.

Jeff.
Click to expand...

The switches I'm using right now on robot control boards are simple single pole pushbuttons, but they have four contacts - one in each corner so that they mount solidly on the PCB. The pairs of contacts on each end are wired together internally so you can use one or the other. It's a mechanical thing, not electrical. The trick is to not install them rotated 90 degrees...

http://www.mouser.com/ProductDetail/ALPS/SKHHAMA010/?qs=/ha2pyFadugu8I2tvG3Spq0ZWIPwNOK0vHML1LtnMH8=
 
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Shorty,

I only have one seat. No need for two switches. Building a single seat EAB. :hairraise:


Jeff.
 
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