ICOM IC-208H extended Rx and Tx mod

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BlueMurder
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ICOM IC-208H extended Rx and Tx mod

Post by BlueMurder »

Is the below link the same procedure you guys in the know would use or have used to extend Rx and Tx on your IC208H.
I come across it on the interwebz and thought i would check in to see.
Much appreciated everybody.

http://www.hampedia.net/icom/ic-208h-ex ... tx-mod.php

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Phantom
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ICOM IC-208H extended Rx and Tx mod

Post by Phantom »

All I can suggest - if you are asking about the mod to expand the range of the 208H - then one would guess that you should not even be mucking around with the insides of any radio

By the sounds of it - you may be on the quick path the turning a good 2/70 radio into a brick!

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youngn
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Re: ICOM IC-208H extended Rx and Tx mod

Post by youngn »

Does the IC-208H come with UHF CB out of the box???
"YOUNGN"

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Phantom
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ICOM IC-208H extended Rx and Tx mod

Post by Phantom »

Rx only (out of the box)

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878ROB
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Re: ICOM IC-208H extended Rx and Tx mod

Post by 878ROB »

I done this mod to my 208H... easy mod, please do not attempt if you dont have a super dooper eyesight or magnifying glass as the 2 resistors are very small, my radio worked perfectly fine after i did the mod...
878 ROMEO OSCAR BRAVO Bleeding through a television near you!

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jaskel
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Re: ICOM IC-208H extended Rx and Tx mod

Post by jaskel »

Same here, worked a treat for me! the resistors basically break apart once u heat them.

TX and RX on UHF CB fine.

The output is far lower than what u get from 2m or 70cm.
Uniden UBCD996XT, UBCD396T,Pro 96, UBC120XLT, Icom IC-208H, GME TX4220, Icom IC-F410, Discone

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878ROB
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Re: ICOM IC-208H extended Rx and Tx mod

Post by 878ROB »

yes you should not operate the radio at full power!!!! keep it around mid level to keep the ass end happy...
878 ROMEO OSCAR BRAVO Bleeding through a television near you!

ozstickman
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Re: ICOM IC-208H extended Rx and Tx mod

Post by ozstickman »

Thats what amps are for....

ozstickman
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Re: ICOM IC-208H extended Rx and Tx mod

Post by ozstickman »

after my old UHF CB dieing the other week I thought I'd give my 208 a go as a UHF CB but I have discovered that the SWR is way too high, it was up around 4:1. Yes I did check to make sure the antenna and lead was in good condition. I checked it on my other car with a TX4400 and got a SWR of 1.5:1.

So with this I say would not recommmend TXing on the 477 CB range too much.

melbourneradio
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Re: ICOM IC-208H extended Rx and Tx mod

Post by melbourneradio »

Not a good idea .. not going over this again .. but really people still dont get it

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Schermann
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Re: ICOM IC-208H extended Rx and Tx mod

Post by Schermann »

Please, how to REVERSE this mod?

Image


Does anyone know how to reverse this so that an IC-208H can be returned to AUS spec and lock out any TX on the UHF CB band?


Ok, here is the matrix diode list from the Icom IC-208H Service manual pertaining to TX/RX bandwidths.

http://www.radiomanual.info/schemi/IC208H_serv.pdf

Image

...and here is the Matrix schematic from the service manual showing the 16 slot configurations for the S.Diodes (not resistors)!

Image

NOTE: Position indicated above at D508 corresponds to the AUS spec but is that the only diode that is to be put back???

Any ideas as this is not covered anywhere!

:?:

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