home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
World of Ham Radio 1997
/
WOHR97_AmSoft_(1997-02-01).iso
/
mods
/
icom
/
icom_r
/
r7100_01.doc
< prev
next >
Wrap
Text File
|
1997-02-01
|
2KB
|
43 lines
Subject: Re: R7100 Modification
Ever since ICOM decided to delete the 800 - 900 MHZ coverage from its
IC-R7100 receiver, older R7100's demand premium prices on the used
market. ICOM insisted that the R7100 was now made in two versions, one
for the general public and another (with 800-900 coverage) for
government and law enforcement agencies. The extended coverage version
also sells for $200-$300 more! Per discussions with ICOM there were
very clear that this was done to comply with legal requirements that
prohibit new scanners from be capable of receiving cellular telephone
transmissions. My opposition has always been why we should be
penalized if we want to listen to local law enforcement agencies within
the 800 MHz band. Personally, I have no interest in listening to cell
phones when a receiver as competent as the R7100 opens up almost 2 ghz
of spectrum.
I recently noticed that Grove now offers the R7100 with "restored"
coverage so I set out to find out how it was done. Performing the
following procedure will allow you to listen to local law enforcement
with the 800-900 mHz portion of the spectrum. Remove the screws that
hold the top cover and disconnect the speaker. Next, remove the two
flat head screws that hold the metal shield covering the rear of the
front panel.. On the rear apron, remove the two screws that hold the
upper chassis to the lower chassis. Finally, remove the antenna cable
that is connected to the circuit board assembly in the rear right
corner of the R7100. Referring to the owners manual, CAREFULLY separate
the upper half of the receiver, inverting it, setting it beside the
radio as illustrated in the owners manual. Be careful not to pull on
the cables that connect the upper portion to the lower half of the
radio. In the front of the owners manual there is a small paragraph
that explains the various jumper options for the R7100's CI-V interface
options. It's on this board that the modification is done. The board
is located behind the "M-SET" switch. The jumpers are actually circular
pads, split vertically. A drop of solder constitutes a jumper - no
solder = no jumper.
Locate jumper "A6" as illustrated in the owners manual. Above "A6"
you'll see a small ball of solder. Using solder wick, CAREFULLY remove
the solder, exposing the split circular pad beneath. The space between
the pads is very small so be sure to remove all the solder. Reassemble
the radio and you're done!