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QRZ! Ham Radio 13
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QRZ Ham Radio Callsign Database - Volume 13.iso
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ft221r.txt
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1999-04-07
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Date: Tue, 17 Jun 1997 00:14:49 EDT
From: wa4oba@juno.com
To: sba3020@InfoNET.st-johns.nf.ca
Subject: Re: Yaesu FT221R repeater mod.
UPDATING THE YAESU FT-221R
With the recent opening of the 2-meter sub band [144.5-145.5 MHz] to
repeater operation,owners of some excellent transceivers find themselves
unable to use their rigs to key machines on the newly activated
channels.Notable among those radios is the Yaesu FT-221R.In order to
prevent out-of-band operation,only the 146.5MHz and the 1470-MHz switch
positions permit offset transmission.Yaesu engineers did not anticipate
the recent FCC ruling and as manufactured,the 221R cannot work through
repeaters having inputs below 146.0-MHz.The solution I describe below is
simple and does not mutilate the radio.Only two short pieces of wire and
one new offset crystal are required.
Loosen the top cover by pulling up on the four snap fasteners and
carefully pry off the cover.Turn the set upside down on the work table
.Remove the side screws and slowly lift away the bottom shell.The
four-section band switch will be found just behind the front panel.The
second band switch from the panel is designated as S2B, the third section
as S2C.
The solder lugs of each section of the switch [from lugs 1 through 8]
start with number 1 on the left UNDERSIDE of the wafer [looking from the
front panel].Number 2 is the first lug on the left TOPSIDE.Number 3
through 8 follow clockwise so that number 8 is on the extreme right
TOPSIDE of the wafer,as you view the switch with the set upside down.
On the wafer S2B solder an insulated wire about 1-1/2 inches[40 mm]
long to lugs 3 and 7.Lug 3 is not wired at the factory,and lug 7 has a
yellow wire soldered to it. On S2C connect lug 3 to lug 6.Again,lug 3 is
not factory wired; lug 6 is solder to a dark blue wire. Be very
careful,when soldering,not to melt the insulation of surrounding wires. A
helpful idea is to have a friend use to small screwdrivers or similar
instruments to separate,and make a path through,the jungle of wiring
around the switch while you do the soldering.
Now replace the bottom shell. Turn the radio right-side up. Remove the
black plastic cover plate over the LOCAL board and carefully pull out the
board. Just rock and lift it gently out of its edge connector. Plug a
13.9666-MHz crystal [case type HC-25/U ] into position 12 on the offset
/ auxiliary end of the crystal strip.Do Not use socket 9.
At the bottom of the component side of the LOCAL board find connector
contacts 28 and 30. They are contiguous to each other. Immediately above
the contact strips very carefully solder [ with a low heat iron ] a
bonding bridge connecting the printed conductors of 28 and
30.Then,immediately above this solder bridge sever the pc conductor of
number 30. Use a razor blade,or X-acto knife.Be sure the 28 to 30 bridge
remains intact. Replace the LOCAL board in the chassis-mounted
edge-connector. Screw it down tightly.
Turn on the transceiver. Rotate the band switch to 145.0 MHz.Throw
the AUX switch to the UP position and the RPT switch to NORM. Key the
transmitter [ with dummy load ] and adjust the trimmer capacitor of
crystal 12 [ last one on the left , looking from the front panel ] until
the transmit frequency is 600 kHz lower then the receive frequency.
Replace the plastic cover plate over the LOCAL board. Replace the top
cover. The set should now operate through the repeaters on the 144.5-to
145.5-MHz sub band... And surprise!! You are also able to use the 221R
on 1-MHz split repeaters in the 146/147MHz "oddball" band. Just turn the
band switch to 146.0 MHz,the AUX toggle UP, the RPT toggle to either NORM
or REV, as the occasion requires,and you've got 1-MHz split without the
need for an additional crystal.You're actually using one of the
factory-wired crystals as an offset rock without impairing the normal
function.
When I ordered my crystal I also ordered The frequency I use as
simplex and that saves a lot of tuning.I ordered Mine from "Jan
Crystals",They charge as much for one as they do for two.That was the
reason I ordered the simplex one
NOTE: On the LOCAL board contacts at the bottom of board there will be
6 or more contacts in a row then a blank and then another one .The two
that are bridged together are the last two before the blank space.The one
you cut is next to the blank of the two you bridge together.I hope I have
not confused you to much .Have fun!!
73s
Herman A.Tucker
wa4oba@juno.com