Elevator Trim switching arrangements

I am instaling a MAC (Now RAC) elevator trim servo in my very slow build RV-6 and wish to install two trim switches, one a "coolie hat" in the LH stick, & one the MAC rocker switch in the panel.

To achieve this I gather from studying the current Ray Allen Co website that I need to rewire the RS2 Rocker Switch, add two diodes & wire in a REL-2 Relay Deck.

I have seen talk of the MAC/RAC relay decks failing and I note that the REL-2 has replaced an earlier model.

I also note that Matronics sell a Mk III Governor to replace the relay and it also contains an adjustable trim speeed function & is claimed to have several advance functions, like accomodating opposite switch commands.

Has anybody had experience with either the RAC REL-2 relay or Matronics governor?

Any feedback, recommendations, & advice would be highly appreciated.

Thank You
Graham Murphy
New Zealand.

Graham,

I can't speak to the RAC relay deck specifically. I am using their trim servos, but made my own relay deck drived from a stick-mounted switch. The relay deck is as simple a device as you can make. I will probably make a more fancy version once I am flying with solid state motor controllers and variable speed. For now, 4 relays, 4 diodes, some proto board, and wire is all it takes.

I got my relay board from Infinity (the same place I got my stick grips), so I can't attest to the durability of the MAC/RAC relays. I've got about 85 hours on my RV-6A and no problems.

Jim Bower
RV-6A N143DJ

Gents,

Thanks for the useful replies. Since postingthis I phoned Ray Allen Co & spoke to Scott who was most useful.

My rocker switch was delivered in 1999, and Scott informed me that they have since developed a new model with a firmer feel and which looks completely different internally. The rewiring instructions are based on the new switch.

BUT what ther documentation doesnt make clear is that if you fit two diodes inline to the RS2 switch as shown in their wiring diagram for combining a 4 way switch and a rocker switch, and wire the red wire to earth & disconnect the black wire as shown, then you DO NOT have to rewire the RS2 switch as instructed on the same document!!

Thanks
Graham