[ICOM] ICOM H6 programming help

[Ernie Howard]

Gary

We had some of these radios that I maintained where I work. Our crystal 
frequencies didn't conform to your chart either. We had some that were 154 
to 159 and some that were 150 to 155. We specified to Icom what 
frequencies that we wanted to cover, and they supplied the proper crystals 
to work that band segment. So don't get hung up on the ranges in the book.

Now I am a bit foggy on this, it has been a long while since I worked on 
them. There is a special formula that you could use to calculate the 
'divide number'. You then entered the divide number on the diode board.

I can recall doing this several times to change frequencies, but I no 
longer have the information that I used to calculate or the formula. But 
the formula is in the service manual.

I did download the service manual off of mods.dk web site. On page 7 of 
the PDF copy, (section 3.3.3, their page 3-2) there is the formula to 
calculate the 'divide number'. You use that divide number in BCD format on 
the diode matrix board. If you look across the board, you should be able 
to verify the load number for each of the existing channel's frequency. 
Each digit of the load number is on a column and each channel is on a row.

Hopefully that headed you in the right direction.

73 Ernie W8EH




> Original xtal frequencies were as follows.
> 
> operatig frequency range     X202               X203
> 
> 150.005 ~  155.000          32.02626          36.25125
> 
> 155.005  ~  160.000          33.27625          37.50125
> 
> 160.005  ~  165.000           34.52625          38.75125
> 
> 165.005  ~  170.000           35.77625          40.00125
> 
> In it are 33.070 for X202,  and  37.305  for X203. Rather strange
>