A Brief History of the Yaesu FT-101
By Chris Arthur VK3CAE
During the 1970's, Yaesu's
FT-101 model of transceiver was well known to radio amateur's
throughout the world. The Image to the left shows an early 70's model, it was by
no means what you would call "at the cutting edge", even then.
However, the FT-101 was an economical, robust radio with reasonable performance
and it was these qualities that lead it to be a top seller of that era. Here is
how the FT-101 progressed through the 1970's to become one of the most popular
HF amateur rigs of all time (As per
1971 (Early) the early
FT101
This unit can be identified by the absence of the 160 Mtr band and by the use of Two output transistors on the
audio unit. The main complaint with this early 101 was that it suffered from
cross modulation and receiver overload on 80 & 40 when hit with a big
signal.
1972 (Mid) FT101 Mark 1
Basically the same as above except the Audio
output transistors are replaced by a large Audio IC from Sanyo, (easy to spot
with the lid off) giving slight improvement in recovered audio quality.
1972 (Late) FT101 Mark 2
This unit showed considerable improvement over the mark
1, with the addition of 160 Mts and quite a few
technical refinements. Larger heat sinks and transistors on dc-dc inverter, new
IF circuits and the addition of a Noise Blanker (on top of VFO). Together with extra filtering improved performance greatly.
1973 (late) still Mark 2 but an extra Receiver Audio pre-amp is fitted behind mode switch.
1974 (Early) Early FT101B
Changes are, two LED's on the front panel for
CLAR and VFO active, internally the Noise Blanker PCB is moved to plug in
behind the MIX and HF IF PCB. Plus, the addition of an eight pole SSB filter
improves selectivity.
1975 (Mid) FT101B Mark 1, Large Sanyo IC dumped for smaller more powerful IC.
1975 (Late) FT101E Mark 1
This unit is the same as a B Mk 1 but has the
addition of a Speech processor, this early Processor was not very popular as
there was no external Level Adjustment.
1976 (Mid) FT101E Mark 2
In this model speech processor is redesigned, it is
identified by CLAR/LEVEL dual gang pot on front panel, I had one of these units
for about ten years.
1977/78 FT101E Mark 3
The last of the true 101 series, with this
model the DC/DC converter is further reduced in size and the Noise Blanker
circuits are rehashed for better noise rejection.
1978/79 FT101ZD
This was an entirely new design and used the
101 number for marketing purposes.
In the 80's and early 90's I brought several
101's mostly in poor condition, I read the workshop manuals, worked on the
radio's and became quite familiar with them but that's somewhat in the past for
me as I've moved onto other things. There is now a great deal of Web based
information on the Yaesu FT-101, with the most
comprehensive being compiled by Al
Rabassa, NW2M, this site is a must see for all
101 fans.