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RE: New S Band Converter



> *** 2m 23cm IF, 70cm 13cm IF

Probably the most common scenario.

> 
> Pro's:
> 
> o Easy to find 23cms uplink trasmit converters on 2m.
> 
> o Fairly wide 13cm sub-band available to you.

In some areas (e.g. Australia), may simplify choices for 13cm Rx (common
converters from defunct pay TV systems here have a LO of 1951 MHz, so 2400
MHz becomes 449 MHz, which could be reached with a slightly modified 70cm
Rx.

> Con's:
> 
> o Your expensive 23cm Transmit converter will likely be very 
> narrow band on
> 2m and be limited to the satellite sub-band (1268MHz).

You will need separate xtals for satellite and terrestrial, unless you can
mod your IF Tx/Rx to go out of band.

> Pro's:
> 
> o Nice wide band transmit, likely to be able to use TX converter for
> terrestrial 23cm too. (You'll need to mod your FT-847).

Generally, this is the case, most rigs only cover 10 MHz out of the box
here.

> o May be difficult to find 70cm IF TX converters. I think 
> there may be a
> technical consideration in using a 70cm IF due to local oscillator
> considerations and in band transmit mixing products.

I'd imagine this is a similar scenario to 2m -> 70cm, but I happen to have a
2m - 70cm transverter.  It uses double conversion, down to 10m, then back up
to 70, to avoid any spurious products leaking through the chain.

> o Very limited sub-band of 13cm available to you.

In VK, not an issue.  only need to cover 2400 - 2404 MHz for terrestrial and
satellite operation (our terrestrial is conveniently on 2403 MHz).  
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