From: N295P@aol.com
Message-ID: <d4578d85.3676087e@aol.com>
Date: Tue, 15 Dec 1998 01:58:06 EST
To: lancair.list@olsusa.com
Subject: Avionics trays
Mime-Version: 1.0

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Dear LL:
All tray avionics will come with a tray as part of the kit. They will supply
enough pin connectors to interface with as many connections as you need at the
rear of the tray. I used a Century 2000 autopilot, it came with a tray and a
66% wired harness that you need to interface with HSI-VOR/OBS displays. Lots
of wires to match up for all the flag and indicator drivers. Probably best to
stick to one avionics brand primarily for aesthetics. You will be reading some
complex schematics.

All tray avionics will be 6 1/4" wide and a variable height. Note that the
height will be greater than the stacked trays, as the individual trays may be
shorter than the full height of the radio. Mock up the stack and leave a
0.032" spacer between the faceplates as a shim (discarded at final assembly,
of course). The face of the radio will usually be the highest part of the
unit: insure that they are level to each other by using a 1/4-3/8" wood shim
at the rear part. On the IV, make sure that you have enough depth for a given
instrument+connectors. The 3 1/8" hole mounted instruments mount at the face
but the long ones (HSI, GEM) will need some structural connection at the rear
as they are heavy. 

Be especially careful of clearances for the deep instruments at the sides
where the panel is angled out, at the top because of the glareshield that
slopes down and finally at the aileron interconnect tubing at the very base of
the panel. I did all my avionics, prewired my radio stack, then the cables to
the HSI and Horizon and intercom. Do as much as you can before placing in the
plane. Do subunits, leave wires to be connected longer than you possibly think
you will need. 

Robert Forest
N295P