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-   -   Yaesu FT221,221R and derivatives (https://www.vintage-radio.net/forum/showthread.php?t=144766)

Jon_G4MDC 14th Mar 2018 12:58 am

Yaesu FT221,221R and derivatives
 
I have spun this out from another thread.

My apologies for not checking what has gone before on this forum but these sets are so well regarded I think they deserve a thread to catch their history before it is lost and gone.

I will start with my own observations...

The power connection arrangements are nasty and perhaps dangerous. Jones plug for AC and 12V - how to make it safe?

The AM/SSB modes have no squelch. Most annoying. Happily I have a fix for that.

The VFO can develop "tight" spots which really takes away the pleasure of a fine feeling dial. What are the causes and fixes?

Mutek front ends can be found in some. There are different RF circuit variants depending on age.

AM RX is run through the SSB RX path - it is not great as a result. By comparison the AM TX seems quite good.

Anyone like to add more or discuss perhaps?

M0AFJ, Tim 14th Mar 2018 4:25 pm

Re: Yaesu FT221,221R and derivatives
 
I'd be looking for the FT225RD to be honest, a significant improvement to the FT221.
I've seen them in pretty good condition for less than £150 and they can still hold their own in a contest environment.


Tim M0AFJ/G8GGP

Jon_G4MDC 14th Mar 2018 6:15 pm

Re: Yaesu FT221,221R and derivatives
 
What did they change apart from the dial readout please Tim?

I have never had one but I cant see much change in the schematics - not that I have looked that hard.
That would be all good info and so part of the reason for starting the thread. :)

M0AFJ, Tim 15th Mar 2018 11:43 am

Re: Yaesu FT221,221R and derivatives
 
It’s been years since I had both but from what I remember the front end filtering on the 225RD was improved as was the local oscillator/ mixer, I might be wrong, the brain doesn’t work as well as it did!

Jon_G4MDC 15th Mar 2018 5:42 pm

Re: Yaesu FT221,221R and derivatives
 
Thanks, Yes on a second look I do see differences in the front ends.
They went from a JFET mixer 2SK19 to a dual gate MOSFET 3SK51.

Of course once you have a Mutek you have a 3SK88 or BF981 in RF amp and a diode ring as mixer.

M0AFJ, Tim 16th Mar 2018 10:24 am

Re: Yaesu FT221,221R and derivatives
 
The Mutek boards certainly made them fly, I worked all over the place on mine from near Wrotham back in the day, mind you the 4CX350 and 16 ele Tonna helped :)


73


Tim


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