Terra TX720 schematic ...

[Ron Gleason]

I have searched RAS for this topic and could not find specific answers so ...

The local club here in Northern Utah has acquired a new Grob Twin Astir with a Terra TX720 radio installed. The radio is working but the On/Off and volume switch has flat spots and we would like to replace it.

Does anyone have the schematics for this radio? Or does anyone know the exact switch that is needed (no markings on the existing switch).

Thanks in advance

Ron Gleason

[Charlie M. (UH & 002 owner/pilot)]

On Tuesday, April 14, 2015 at 11:57:09 AM UTC-4, Ron Gleason wrote:
> I have searched RAS for this topic and could not find specific answers so ...
>
> The local club here in Northern Utah has acquired a new Grob Twin Astir with a Terra TX720 radio installed. The radio is working but the On/Off and volume switch has flat spots and we would like to replace it.
>
> Does anyone have the schematics for this radio? Or does anyone know the exact switch that is needed (no markings on the existing switch).
>
> Thanks in advance
>
> Ron Gleason

Redo your search, but use "tx-720" instead. There are quite a few threads that will pop up.

IIRC, Gary Kemp had info on the radio, but it's an older thread.

[Burt Compton - Marfa Gliders, west Texas]

Search
http://www.esscoaircraft.com

Essco website shows they have a paper or downloadable manual in stock for $30.
A good investment if you plan to keep this older radio.

[Ron Gleason]

Thanks Burt. We will see what the club wants to do.

[Craig Funston]

On Wednesday, April 15, 2015 at 9:52:17 AM UTC-7, Ron Gleason wrote:
> Thanks Burt. We will see what the club wants to do.

If it's a simple switch + potentiometer you may be able to measure resistance at several points and find a replacement at Mouser or somewhere like that. If it's just a dirty pot, you may be able to use some cleaner on it and get a few more years out of the existing one.

Good luck,
Craig

[Ron Gleason]

On Wednesday, 15 April 2015 11:28:22 UTC-6, Craig Funston wrote:
> On Wednesday, April 15, 2015 at 9:52:17 AM UTC-7, Ron Gleason wrote:
> > Thanks Burt. We will see what the club wants to do.
>
> If it's a simple switch + potentiometer you may be able to measure resistance at several points and find a replacement at Mouser or somewhere like that. If it's just a dirty pot, you may be able to use some cleaner on it and get a few more years out of the existing one.
>
> Good luck,
> Craig

Thanks Craig. We have some measurements but the number appear high (I am not a electronic guy) and were hoping to get actual specs before we looked around for a replacement.