IC-M700 Marine HF SSB reviewed for Ham Radio

Описание: Let's look at how well the Icom IC-M700 Marine HF SSB radio from the 1980s works for ham radio. We'll look at basic usage, repairs, and modification. Stick with it, there are some long gaps I accidentally left in, but you can see the details of the SRAM upgrade and the audio speech processor install.

Full schematic of SRAM Memory Expansion:
https://gitlab.com/eliggett/ic-m700-mods
Read-Me file:
https://gitlab.com/eliggett/ic-m700-m...
Schematic:
https://gitlab.com/eliggett/ic-m700-m...
Microphone schematic (unavailable anywhere else):
https://gitlab.com/eliggett/ic-m700-m...

How to add 10/11M (edit the SRAM contents and then retune the VCO):
   • ICOM M700TY for CB Band #Injectramboard  
Notice that the hex editor shows the frequencies nearly in plain text:
050432ff050432 (RX and TX) is the frequency 23.4050. It's just backwards. The IC-M700 does not have any special "configuration bits" in the SRAM; it is ok to erase entirely.

Lastly, I'm sorry about the audio quality here. The microphone slipped inside my shirt and it frequently distorted! I've tried to at least turn it down during the worst clipping so that it isn't too awful.