Mods for Radio Shack Tranceivers
David Duerksen
yet) and I was given two radio shack trancievers. they are the HTX-202
and the HTX-404. The 202 is a 2 meter unit, and the 404 operates
between 430MHz to 450MHz. Since they were free, I guess I can't beat the
price. But I was wondering what kind of modifications I could make to
them, and how I'd go about doing it. These may seem like stupid
questions to some, but I'd appreciate any help y'all could give me.
Thanks again in advance...
Dave
D
D
Plea
Pat McCarty
: Hi, I'm REALLY new to all this (in fact, haven't even gotten my license
:
: Thanks again in advance...
: Dave
OK, I dont know about if any of this is true, but I have a HTX-202.
I got this info off of ftp.qrz.com
Subject: HTX202 NOT MODIFIABLE
Greetings HTX-202 Fans:
It seems that human nature dictates that every major item we purchase be
"hot rodded" into something other than what the manufacturer intended. Our
first car, our first radio, and now: the HTX-202. Regardless of the total
lack of necessity for most owners, everyone wants to broad-band the 202.
Perhaps in our evolution, there is a little CB radio mentality left under
the surface. Who knows? But hopefully, I can answer a few questions which have
yet to be answered to the ham community.
The HTX-202 is based on the ICOM 02AT with certain design modifications
besed on Tandy's specs. These variations include encode/decode, additional
memories, and a full width LCD display. Contrary to rumor, no part of the
radio is Kenwood or Yaesu! ICOM sold the rights to their design to Tandy to
do with what they would.
Whan Tandy sought to produce the unit, they went to their usual Korean
source for cheap gadgetry: MAXON. Maxon then built the 202 for Tandy, under
license from Icom. The HTX-202 is surprisingly sturdy, and well constructed,
considering that Maxon has the worst quality control in the industry.
Be that as it may, before Tandy would produce the 202, certain specs
had to be met. Foremost, after the repercussions from their 10-meter rig,
Tandy insisted that the 202 NOT BE CAPABLE OF MODIFICATION! Period.
This worked out well, as the tighter bandpass gives the 202 it's
exceptional selectivity and immunity to intermod. When you brag to your
friends about your tight front-end, just remember that the cost of this
important function, is the lask of ability to kerchunk your local police
department's repeater. Why complain anyway?
Most 202's will not take a BP-7 Icom pack. The BP-8 usually works well.
If the Zener diode in the bottom-feed circuit is bad, only a 9.6-vdc pack
or less will work. A minor headache at the very least.
ALWAYS: Slide off your NiCad pack when using external DC power from
your vehicle or a power supply! Leaving the pack on while mobile puts too
much burden on the Zener diodes, and generates heat at twice the normal
rate. Save your radio... Take off the pack!
Unlike it's Icom brother, the 202 will not top charge an Icom pack
while on external DC power. Refer to the warning above!
HIDDEN FUNCTION: Holding the <F>unction button while depressing the
<L>ight button will cause the display lighting to remain on until the
<L>ight button is pressed again.
HELPFUL HINT: Discard your belt clip... Install a commercial H.T.
"D-swivel" available at any FM 2-way Business Radio dealer. Add the mount
to your belt, and VOILA... No more dropped radios.
WARNING: DO NOT ATTEMPT TO BOTTOM-CHARGE THE STOCK NICAD PACK IN AN
ICOM BC-35 OR CLONE CHARGER. NEVER, NEVER, NEVER!
DESIGN FLAW: Some early production (S/N 2500 and down) radios had the
NiCad Zener Diode located too close to the finals, causing final transistor
failure when used on external DC with the pack in place. This was remedied
in production, and Tandy will remedy under warranty.
Hopefully, this will address all remaining questions and rumors in
regard to the HTX-202. It can't be modified. Big deal! It is a sturdy, well-
built, dependable radio and a bargain at the price. Be happy with a great
deal on a great radio. My HTX-202 got me through in an emergency situation,
where my 800-MHz commercial trunked radio failed... That's more than
enough for me!
----- 73 de Jim. N9PEK @ WB9SLE.IL.USA.NA
P.S.: TNX Tandy... For once, I'm a happy customer!
Whelp there it is...
-- Pat
KE6YOU
Geoffrey S. Mendelson
: The HTX-202 is based on the ICOM 02AT with certain design modifications
: besed on Tandy's specs. These variations include encode/decode, additional
: memories, and a full width LCD display. Contrary to rumor, no part of the
: radio is Kenwood or Yaesu! ICOM sold the rights to their design to Tandy to
: do with what they would.
This is an "urban legend". Icom had nothing to do with th htx-202. The
ICOM story was invented by R/S salespeople to sell more 202's.
They have been told not to do it (I've seen both the ICOM to R/S letters
and the R/S letters to their salespeople), but it persists.
They do use the same batteries as some older ICOM radios.
Some headsets will work, but the later ICOM ones use a three connector
plug on the mic instead of the R/S two connector plug.
IMHO the htx-202 is a good value for the money, but it is poorly made
compared to ICOM and Motorola radios. I don't have another brand ht's so I
won't comment on their relative quality.
I have 2 htx-202's and both have been in the shop twice. The service plan
is a necessity.
73,
Geoff.
--
Geoffrey S. Mendelson (N3OWJ)
President, Mendelson Computer Consulting, Inc.
Voice (215) 242-8712 Fax (215) 242-3116 Email: g...@mendelson.com
Gary Coffman
>David Duerksen (blk...@quack.kfu.com) wrote:
>: Hi, I'm REALLY new to all this (in fact, haven't even gotten my license
>: yet) and I was given two radio shack trancievers. they are the HTX-202
>: and the HTX-404. The 202 is a 2 meter unit, and the 404 operates
>: between 430MHz to 450MHz. Since they were free, I guess I can't beat the
>: price. But I was wondering what kind of modifications I could make to
>: them, and how I'd go about doing it. These may seem like stupid
>: questions to some, but I'd appreciate any help y'all could give me.
>
>
>I got this info off of ftp.qrz.com
>
>Subject: HTX202 NOT MODIFIABLE
Some of that was true, some false. Truth, the HTX-202 isn't designed
to permit operation way outside the amateur bands (a good thing IMHO).
Any "mod" the purports to do so is a fake. Tandy denies that any of
the radio's technology was licensed from Icom, and a side by side
comparison of the schematics seems to confirm that, though it was
designed to accept Icom accessories such as spkr/mics and battery packs.
Yaesu also uses roughly the same spkr/mic circuit, as do some of the
third tier manufacturers, Icom set a quasi-standard in that regard.
Truth, Maxon does make the units under contract to Tandy. The zener
diode overheating babble was just that, babble. The steering diodes
are just ordinary diodes, and they shouldn't get hot in normal operation.
There are a number of good reasons why you don't want to run the radio
off of higher than recomended voltage, but this isn't one of them.
Gary
--
Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems | we break it. | emory!kd4nc!ke4zv!gary
534 Shannon Way | Guaranteed! | ga...@ke4zv.atl.ga.us
Lawrenceville, GA 30244 | |
Craig Petersen
>
>Hi, I'm REALLY new to all this (in fact, haven't even gotten my license
>yet) and I was given two radio shack trancievers. they are the HTX-202
>and the HTX-404. The 202 is a 2 meter unit, and the 404 operates
>between 430MHz to 450MHz. Since they were free, I guess I can't beat the
>price. But I was wondering what kind of modifications I could make to
>them, and how I'd go about doing it. These may seem like stupid
>questions to some, but I'd appreciate any help y'all could give me.
>
>
>
> Dave
>
>D
>Plea
Hello, the units you are refering to CANNOT be modified. I own a HTX 202 and
it has given me years of faithfull service. When Radio Shack had these rigs
manufactured, they insisted that they be built so they can't be modified in
any way......Hope you have fun with them.....Seeya N7UQA
Val Breault
> Hi, I'm REALLY new to all this (in fact, haven't even gotten my license
> yet) and I was given two radio shack trancievers. they are the HTX-202
> and the HTX-404. The 202 is a 2 meter unit, and the 404 operates
> between 430MHz to 450MHz. Since they were free, I guess I can't beat the
> price. But I was wondering what kind of modifications I could make to
> them, and how I'd go about doing it. These may seem like stupid
> questions to some, but I'd appreciate any help y'all could give me.
You have two very good radios there. They aren't small, they aren't
flashy, they don't play games and they don't make very good scanners.
They *ARE* however very good two way radios. They have great audio,
their output power is conservatively rated at 5W max, they are rugged
and they will work in areas where the radio interference makes other
radios useless.
They accomplish that last point by being engineered as a HAM BAND ONLY
radio. The front end is specifically narrow banded such that even if
you could get it to receive out of band (you can't) the signals can't
make it through the narrow filtering.
I own one of each and love them both. My HTX-202 has been running
continuously for several months now as my packet radio. (Like a
telephone BBS connection without the telephone line.)
I know of no modifications for either.
All that aside. I wish you well in your goal of getting an amateur
license. (You didn't say you were going to get one, I just presumed
that.) Please let us know how you're doing and don't be afraid to ask
for help or advice.
Oh... Don't let any grumpy old men rain on your parade.
--
Val Breault vbre...@gmr.com \ /| ars N8OEF
GM R&D Center - instrumentation dept. \ / | pres GM ARC
My opinions are not necessarily those \ /__| HF mobile on
of GM R&D or of the GM Corporation. \/ |___ 14.200 +/-
Tom Randolph
In article <1995Oct4.2...@gsm001.mendelson.com>, gsm...@gsm001.mendelson.com (Geoffrey S. Mendelson) writes...
>IMHO the htx-202 is a good value for the money, but it is poorly made
>compared to ICOM and Motorola radios. I don't have another brand ht's so I
>won't comment on their relative quality.
If you say so.
However, I live two miles from a big commercial/public service site. I'd be
able to see it out the front door if it wasn't for the trees. The HTX202
receives weak signals among the pager trash, while my Icom IC2-AT, reputed to
be one of the best performing/most rugged radios they made, gets totally
stomped and goes deaf as a post. At hamfests, the Icom is useless. So much
adjacent channel crud that the desired signal is totally covered. I'll be
checking the HTX202 in this environment tomorrow, weather permitting!
YMMV, as they say.
-Tom R. N1OOQ rand...@est.enet.dec.com
Tom Randolph
In article <453l1o$b...@mrnews.mro.dec.com>, rand...@est.enet.dec.com (Tom Randolph) writes...
>In article <1995Oct4.2...@gsm001.mendelson.com>, gsm...@gsm001.mendelson.com (Geoffrey S. Mendelson) writes...
>>IMHO the htx-202 is a good value for the money, but it is poorly made
>>compared to ICOM and Motorola radios. I don't have another brand ht's so I
>>won't comment on their relative quality.
>adjacent channel crud that the desired signal is totally covered.
Following up my own post:
I got to check the IC2-AT and the HTX202 side by side at the biggest hamfest
this side of Dayton on Saturday. This is a good environment for testing the
interference rejection of a radio... tons of signals all over the band, signal
strengths varying by orders of magnitude.
ICOM: Desired signal not copy-able at times due to adjacent channel
interference/intermod/whatever. Wasn't a major problem, because we
happened to pick a channel that wasn't too busy and/or didn't receive
lots of crud.
HTX202: Never heard a peep from any signal that wasn't on frequency.
I still say, the HTX202 is a heck of a deal at $200 brand new. Fire away!
-Tom R. N1OOQ rand...@est.enet.dec.com
Don Boekenkruger
>
>kb8...@delphi.com wrote:
>: Tom Randolph <rand...@est.enet.dec.com> writes:
>:
>: >ICOM: Desired signal not copy-able at times due to adjacent channel
>: > interference/intermod/whatever. Wasn't a major problem, because we
>: > happened to pick a channel that wasn't too busy and/or didn't
receive
>: > lots of crud.
>: >HTX202: Never heard a peep from any signal that wasn't on frequency.
>: Well maybe so, but they don't hold up, you7D be better off spending the
>: extra $$$ and get a better built radio. The HTX 202 is junk, I hate mine
>: I is always in the shop. I won't buy any nore of those cheapo radio shack
crap
>: again.
>:
>:
>I bought one for my wife and one for myself. I also spent the
>extra 40 bucks and got the extended service plan. One radio has
>been perfect for two years, the other was in the shop twice. I
>went back to the store where I bought it on the third problem and
>politely asked for a new radio. The salesman was on the phone
>for a few minutes with the service center and came out unwrapping
>a brand new radio. He handed it to me and I walked out the door.
>They have been rugged, almost impervious to intermod that would
>drive most 'brand name' radios bonkers and they might be 'cheapo' but
>as far as I'm concerned, they've lasted better than any other HT's i've
>had.
>Randy
>WA0TKO
>ra...@aztek.com
>
Well, if you check the specifications of the 202 compared to any
YAESU/KENWOOD/ALINCO/ICOM radio, you will notice that the 202 is far less
sensitive. The 202 is DEAF!
73, de ve7cbt
Don Boekenkruger
do...@direct.ca
Robert L Martin
> Hi, I'm REALLY new to all this (in fact, haven't even gotten my license
> yet) and I was given two radio shack trancievers. they are the HTX-202
> and the HTX-404. The 202 is a 2 meter unit, and the 404 operates
> between 430MHz to 450MHz. Since they were free, I guess I can't beat the
> price. But I was wondering what kind of modifications I could make to
> them, and how I'd go about doing it. These may seem like stupid
> questions to some, but I'd appreciate any help y'all could give me.
>
> Dave
> D
> D
> Plea