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May 30, 2024. The Yaesu FT dx 100 an Amazing Radio for its time!

Another of my Boat Anchors, the FT dx 100. 

This is a truly remarkable radio given it is vintage dating to 1967 and likely a test market radio for its sibling the FT-101. 

BTW I think somewhere near 250K FT-101's were built. I have one of those as well.



This radio has been on You Tube previously but I thought it time to make another video of the FT dx 100. I am impressed with what they could do with Germanium transistors.

Also, impressive is the Linear Reading and Highly Stable Analog VFO. I think this same VFO was employed in the FT-101. 

The Crystal Filter frequency is not unlike that of the HealthKit's at 3.180Mhz (Heathkit = 3.395MHz). A caution for would be homebrewer's thinking about single conversion transceivers using these filters. The harmonics of the BFO or VFO are very close to the range of the Band Pass Filter. Think Double Conversion.

The panel layout with S Meter and VFO Dial Scale is common to many of the Yaesu offerings. 

The radio is a bit weak on the AGC control but hey this was 1967. [There is no waterfall or spectrum display like the FT dx 10 or FT dx 101. OK, I am just poking a bit of fun!]

Check https://www.jessystems.com for a look at how I fixed an earlier FT dx 100 I had. There is also info on that link regarding the radio that exits in few other places on the web. 


That said Yaesu gets an F for the build as there was no thought about how you service parts of the radio. The HV Filter Caps are located in the radio such that you have to remove wiring and many parts just to get access to their solder lugs. Other critical circuits are built into metal boxes that have been soldered shut and no hope of easy access.

If you are homebrewing a radio, then think about DFMA.

Always slightly ahead...

73's
Pete N6QW
34445

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