Convert IC-208H 'general' to AUS spec (NO CB TX)

[Schermann]

I need to Convert IC-208H 'general' to AUS spec (NO CB TX)...
...by soldering on the diode(s) that were left off during production to make it a general version![/B]



Has anyone done it and if you know how, can you tell me how to do it.

Plenty of sites to show you how to mod but nothing on how to un-mod it for Australian use!

I can't use this radio until it is converted to amateur status and this will get a new 208H off my worry list....

eg ...this is to take the US version to 'general' version but where on the board do you re-solder on a new diode to get back to the AUS spec version???



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

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



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!

[Schermann]

Here is what was posted on another forum in answer to my same question...

I've worked with an IC-207h but not IC-208h however they are similar-ish. On the IC-207h some diodes control the RX freqs, some control the TX freqs and others set the country (eg repeater splits etc).

The block diagram in Section 10 Page 45 bottom left hand side and the schematic Section 11-2 also has some more details - info essentially same as those in the parts lists. I would suggest loading:
D508 loaded for [AUS] - this should set the TX limits, this may the only diode you need
D521, D522 - you may need to load these two also (test without first and if radio does not perform like it should then load both of these)

The diodes are all Rohm Semiconductor ISS400 TE61. http://rohmfs.rohm.com/en/products/data ... 1ss400.pdf
It's a basic diode, 80V 100mA SOD-523 surface mount package. Problem is Rohm components are hard to source here, especially if you want only a couple of them! Would suggest an equivalent or direct replacement from au.element14.com (based in Sydney) something like Panasonic DA2S10100L. http://au.element14.com/panasonic-elect ... dp/2459013

Diode cathode is indicated on the package by a laser etched stripe. On the PCB layout the cathodes on the matrox are all facing the outside edge of the board.

Hope this helps. Have fun surface mount soldering!

...and

If you can't solder SMD, could you tin the PCB pads, then solder an 1SS-133 leaded diode to the pads?

Both are high-speed switching diodes.

http://www.datasheet-pdf.com/PDF/ISS133 ... ETC-543625
ISS133 datasheet .pdf - Leaded

http://rohmfs.rohm.com/en/products/data ... 1ss400.pdf
1SS400 datasheet .pdf - SMD

If it's just a diode matrix attached to the PLL programming pins, I bet a commonly-available 1N4148 would even work.

http://www.nxp.com/documents/data_sheet ... 1N4448.pdf
1N4148 datasheet .pdf


...and

Here are the items above referenced for those who are wondering...



- - - - - - - - - - - - - - - - - - - - - - - - -




Thanks, maybe I'll 'hot gun' it or realistically off to iCom for some serious SMD advice...


:You_Rock_Emoticon:

Not sure if it's the definitive answer BUT it's a good start {CORRECTED}

[Vkfour]

Even then, it won't be, "Type Approved", unless is has been certified by an appropriate, authorised person and bears the Type Approval certificate sticker.

[Schermann]

Yes, my title is in error (now corrected),

I'm not seeking 'type approval' because once the TX on UHF CB has been diode disabled then no type approval is required for licensed amateur use on VHF and UHF amateur bands.

ACMA has indicated that this type of diode modification for the IC-208H is acceptable to return it to AUS spec for amateur use.

[Vkfour]

As an amateur, you have the unique legal ability to have, in your possession, any radio equipment at all, provided you do not transmit on frequencies you are not permitted to use, or to use on frequencies that do require type approval, e.g. CB frequencies, on radios that cover both CB and amateur frequencies, (and to operate in excess of your licence conditions, obviously). I know that in the past, some radio inspectors have been over zealous in pursuing people over this sort of radio, but a quick glance at the amateur conditions show otherwise. How many amateurs have HF equipment that has the entire 160 and 80 mx bands on them? How many standard operators have 160, 30, 17 and 12 metres on their radios? And if you go through the frequency allocations, you will find other examples. My FT-60, amateur only, transmits up to about 470 MHz, and it's not a problem provided I don't use it below 430 and above 450. Naturally, if you have non-amateur transmit frequencies programmed in, you're asking for trouble, especially as the Act specifies that the evidentiary burden is on the defence. Note, it is illegal to have in your possession, any equipment designed to specifically monitor anything connected to the public telecommunications system, or to use any radio to monitor such systems.

[Schermann]

As an amateur, you have the unique legal ability to have, in your possession, any radio equipment at all, provided you do not transmit on frequencies you are not permitted to use, or to use on frequencies that do require type approval, e.g. CB frequencies, on radios that cover both CB and amateur frequencies, (and to operate in excess of your license conditions, obviously).

Type Approval is the watch word here, once dioded out this ongoing argument becomes purely academic...

I know that in the past, some radio inspectors have been over zealous in pursuing people over this sort of radio, but a quick glance at the amateur conditions show otherwise.

Pray Tell, who could have have left his Mark as an "over zealous" inspector then???

Naturally, if you have non-amateur transmit frequencies programmed in, you're asking for trouble, especially as the Act specifies that the evidential burden is on the defense.

Note, it is illegal to have in your possession, any equipment designed to specifically monitor anything connected to the public telecommunications system, or to use any radio to monitor such systems.

Yes, this can result in equipment confiscations and overly heavy financial penalties! (Murdoch phone hacking trials)