[Milsurplus] TCS Crystal Control

[Mike Morrow]

Breck wrote:

> I've posted some info on crystal control of the TCS .
>
> I would welcome any additional input on the subject.
>
> http://k4che.com/TCS%20equipment/Crystals%20and%20Adapters/Crystals%20and%20Adapters.htm

The crystal unit for the TCS-series, according to the TCS-7, 9 to 12
manual Navships 900,291-1B (15 NOV 44) is the navy type-40068.  That
is what mine are (COL-40068).

The CHF-40130 unit mentioned in your Hamilton manual must be some
variant that Hamilton devised.

This nt-40068 unit is not quite equivalent to the FT-249, if for no reason
other than dimensional differences:

- The nt-40068 HxWxD is 2.1875" x 1.375"  x 0.9375",
- The FT-249   HxWxD is 2.125"  x 1.5625" x 1.185".

The nt-40068 also has a flat side on the lower right pin...I can't
tell from the photo if the FT-249 does.

The photo you label "Ebay photo   This might be an original TCS crystal"
shows a nt-40068 TCS crystal.  You can see clearly the flat side of the
lower right pin.

The Bendix MX-9E crystal shown is, as stated, a two-crystal unit.  This
particular example was used for channel 4 (4575 kHz) of the ten-channel
AN/ARC-9.  The AN/ARC-9 is the Bendix RTA-1B.  Only commercial model
numbers appear on the AN/ARC-9, but it was procurred for nine standard
USAAF frequencies, plus one channel that varied depending on if the unit
is an early or late model.

Mike / KK5F