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Hams have tended to convert
surplus commercial band radios into amateur use about ten years after
each product dominated the commercial scene. Due to FCC
commercial modulation bandwidth rule changes in the mid-60's, surplus
equipment prices were very low and the performance was very high. Hams
eventually gathered to swap whatever parts and knowledge they had to
share. In fact, this was downright FUN !
1960's
GE's proud tube-type workhorse was known as the the Progress Line.
This is the front-mounted FT36 but most radios were installed into
the trunk with only a control head showing under the dashboard.
The Progress Line was
very popular as a 2-meter ham radio from the late-60's well into the late 70's.
Obtaining this surplus crystal controlled radio with the
optional "four freq deck"
was a matter of on-air discussion and peer envy !
In the mid-60's Motorola came out with what many consider to be the
best transistorized two-way radio introduction in history, the MOTRAC.
The MOTRAC family was seen on Adam-12
and many other cop shows.
Obtaining and
converting these great radios
became a personal goal for many hams. The duopoly-style
competition between Motorola and GE was the subject of more than a few
"Ford vs. Chevy" debates within the ham community .
To compete with the MOTRAC, GE
introduced what many consider to be the greatest flop in two-way radio
history, the GE Transistorized Progress Line or TPL. GE actually
re-purchased many of the dysfunctional TPL's and supplied customers
with the older
tube-type
Progress Lines that actually worked. Only the later iteration of TPL's
(without the quirky delay-line modulators) were
viable but the damage to the GE name took many years to
correct.
Thankfully, the MASTR-Pro and MASTR-II
replaced the notorious TPL. The
GE MASTR-II series was a smashing success. Thanks to some
vibrant third party aftermarket support,
hundreds of MASTR-II ham repeaters are still on the air 30-years later
! The Motorola MICOR repeater also enjoys a similar stature among
hams.
At one time, converting these older
commercial radios presented a very compelling value proposition for
hams. However as more repeaters proliferated, the need to buy additional
crystals for many new repeaters became cost prohibitive. Except
for the hard core enthusiast, commercial mobile radio conversions became the
exception rather than the rule. Of course the off-shore ham equipment
manufacturers eventually dominated the end-user mobile market and with
that, few hams would dare to tinker with these new feature-rich but
almost sealed radios. This
off-the-shelf market dominance continues to this day but some new and highly
relevant exceptions are beginning to appear at hamfests and via eBay.
2003 and beyond Recent FCC rule changes have again mandated
that all new commercial radio systems be capable of "narrow band
modulation" and many heretofore high-end radios are now entering ham
service as surplus. Many well known brand names are showing up
as surplus and the list now includes Motorola, Midland, GE, Kenwood
Commercial Land Mobile and others. The events of the
1960's may be repeating themselves.
This is an example of
only one cost-effective ham conversion, in this case an inexpensive
110-Watt GE Delta which is the big brother to the GE Phoenix. This fifth generation family of GE radios is starting to surface about ten years after their dominant
commercial years. This is a favorite radio for high-performance mobile
use on six-meters for many reasons:
•
very low cost when acquired as surplus equipment
• easy to convert to ham
use
• high operational
performance in terms of great audio and a great receiver
• high transmit power in
most units (and adjustable)
• excellent propagation
on 50 MHz, particularly in hilly areas |
FCC Rules prohibit business-band repeaters on low-band (just below 6M)
requiring that most low-band
commercial radios operated in simplex mode. Due to that limitation,
most mobile radios were manufactured with either 60 or 110-Watt transmitters. If an
enterprising ham can combine the excellent natural propagation of 50
MHz with high mobile transmit power and the utility of ham repeaters, the
resulting performance can be without peer.
This is the most basic
GE Delta S600 control head (tiny too!). The switch modification
on the side provides for two groups of 8 channels for a total of 16.
This fancy 99 channel, GE S950
or S990 Delta
control head
can download sub-groups of frequency/scan data into the synthesized Delta radio below.
The Delta radios change their major option packages by simply changing
control heads. The radio RF drawer remains the same because the
brains and personality are contained within the control head. Much like traditional
ham gear, many radios can be programmed with a PC although these
radios may require a few extra steps.
This deluxe version control head goes for about $35 on eBay.
This resurrected 32ch, 110-Watt GE Delta was reprogrammed for use on
6-meters but variants are also available for the 2m and 440 ham bands.
Depending upon the model, little or no RF conversion or tuning may be
required to reach the adjacent ham bands. The operational performance of these commercial radios often far exceeds that of the typical
off-the-shelf multi-use, multi-band ham radio. These high-power, synthesized workhorse
radios originally sold for between $1500 and $3500. GE Deltas can be obtained
on eBay as surplus for approximately $35-$75 and sometimes come
complete with cables and a basic S600 control head. Depending upon
what is available at the time, you may need to acquire the radio RF drawer, cables and
control head separately. To some hams, if you know what
to look for, "the hunt" is simply part of the fun but this is also
where sharing knowledge through clubs can play a key role.
The final touch.
In a strange twist of fate, the
commercial land-mobile market would no longer support these very
expensive high-end radios and GE finally decided to exit from the
land-mobile business. Under the MA/Com name, Tyco now owns what
remains of the former GE Land Mobile empire but that legacy is now
a subset of what once was a dynasty.
The GE Delta family was only used an as
example of one easy-to-convert radio. Many other commercial
land-mobile manufacturers will soon see their relatively modern,
high-performance radios re-enter ham service as bargain-priced,
surplus gear.
Here we are in 2003 and many hams who enjoy deploying
this gear can be found joining together to swap manuals, expertise and parts.
Hmmm... this sounds more like
"classic" ham radio, doesn't it?
(c) 2003 Rick Zach, K1RJZ |
