Yaesu FT-7900 and the Easy Sats


Clint Bradford
 

A friend asks if he can use his FT-7900 and an HT to do anything with the "easy" satellites ...

ABSOLUTELY!

First, turn the rig's TX power DOWN to 5W ... (g)

And around Page 34 of the '7900's manual, there's a page sub-titled, "Odd Splits." 



These instructions DO work - but using RTSystems' programming software SURE makes 
this task MUCH easier! For Mac or Windows: https://www.rtsystemsinc.com/FT-7900_c_105.html

Program your FT-7900 in Split Freq mode will get you on the FM voice "easy" satellites. If your
DOWNlink is on 440/70cm (S)-50), accommodate for the Doppler phenomenon bu tuning slightly
ABOVE the transmitted frequency to ACQUIRE. If working AO-91 and its 440/70cm UPloink, you will
program your radio to transmit a little BELOW (frequency chart on the home page of work-sat.com ...

It is not "true, full-duplex" though: When you key the '7900's mic on the UPlink, you will not hear
your signal on the DOWNlink. BUT ...

This is where you can use your HT! 

When choosing which radio to use as the receiver in a two-rig setup, I usually like to use 
the radio with the better receiver as my DOWNlink radio. But with satellite AO-91's stong 
2m DOWnlink, you will be able to hear it with your HT and a modest antenna improvement (some 
are actually working AO-91 with STOCK HT ANTENNAS!)

SO ... If you were to purchase an antenna improvement (your Baofeng needs an SMA-FEMALE
antenna), these are great ...

COMET SMA-24 - always 17" long - https://www.hamradio.com/detail.cfm?pid=H0-011735

SMILEY 270 - FEMALE SMA - https://www.hamradio.com/detail.cfm?pid=H0-012996

The Smiley actually out-performs the popular Diamond SHR-320a on 2M - and is HALF the price of
a '320! The Smiley is an antenna that you can keep on the radio all the time: When collapsed, 
it is about the same length as a stock antenna. But when you need improved gain, THAT'S when 
you extend it! But if you are thinking of swapping out antennas on your HT a lot, you may want to invest 
in a suitable BNC-to-FMA adapter: Instead of wearing out your HT's delicate antenna connector (resulting 
in a potential $65 repair job), wear out a $12 adapter instead. The choice is yours ... (g)

So you have your receiver all set up - HT and improved antenna.

For transmitting with the '7900, you want some "directionality" to your signal. Yes, you can increase 
power and use a vertical or mobile antenna. But that's just "sloppy" ops (g). I mean, when you can 
work the ISS when it is 450 miles downrange with just 2W, well, you get the idea). Build yourself a 
tape measure antenna ... or any of the other easy, FUN projects on the ANTENNAS page at
http://www.work-sat.com - I just KNOW you have an un-used steel tape measure in the back of that 
junk drawer!

Operating tips, frequency chart, and a lot more for you at ...

http://www.work-sat.com

And ask any questions RIGHT HERE, too!

Clint K6LCS
909-999-SATS (7287)





 

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