The
ITT starphone UHF FM miniature transceiver for 450-470 Mhz service.
This
little radio first appeared early on the surplus market at about 1983
in the Melbourne and was then available for very little cost.
I
think I purchased mine about 1984 for all of thirty dollars.
It
has provision for 6 crystal locked chanels. It is a pre PLL synthesis
classical crystall locked phase modulated and muliplied up to UHF type
of transmitter. It must have been one of the last of its kind
because the commercial communications market quickly moved over to PLL
designs as customers were naturally reluctant to pay the high price for
cutting dedicated crystals. I think the WIA was selling them
in
bulk, but I cant remember for sure. There are still many in operational
condition. I heard at the time that the CFA had used them but were
dissappointed with the range and let them go in a mass culling, but I
cannot verify that idea.
The power output is a nominal 10 ten
watts but I think in practice the average output was about half that.
The RF front end was as good as late seventies technology permitted and
they did benefit from a change of transistor to something hotter like
an MRF901. I used mine extensively on the upper end of the
70cm
amatuer band where they could be easily retuned to. There are
still a number of these sets still on the air, their conservative
design and thoughtfull layout have given them extended life. I have
still seen these for sale at hamfests at bargain prices.
Here
is
the cleaned up photocopy of the schematics. There is no manual, tuneup
and theory of operation is self evident. The manufacturer
was
ITT. The only indicator was a decal which had parted company with
my set, there is no other clue.
page last updated Thu Apr 10 19:04:41 EST 2008 to improve download times