I like this toy! Handy, comprehensive, batteries not included – what more to wish for? I have been using it at home, on minor expeditions and during several experiments with digital modes. And it still work! Okay, this piece of art is not the best thing ever left a factory, there is a lot of stupid mistakes. Like no cooling fan in QRV-mode on VHF. Poor earth inside. Very strange behaviour when signals are strong. Attaching an active antenna to the HF for some DX-ing was as good as using no antenna at all. Yeah, hearing BBC WC and V.O.R. everywhere is not my way to enjoy radio. But if you want 100 W on HF and 6m, 50W on VHF and 20 on UHF and can stand the mistakes by Yeasu – get one yourself!
Here some tip about improving the ground-system. This might / will help you a lot!
When I had installed my FT-100 and tried it on several bands, I discovered that it could not work UHF without showing high SWR. My problem here was – I had no SWR in the cables! Worked fine with my Kenwood TS-811 and the SWR-instrument showed 1:1. So what’s so spooky about this little black box?
Not until I got myself a CW-filter, I opened the can – and got myself a real surprize! Inside, the cupper-stripes that should improve the ground was barely stacked to the aluminium, and even when I tried to put them back, they loosed again.
So what I suggest, re-place all the cupper-stripe with a better one. I used one from 3M called 1181, 12mm wide (0.5″). It stands for temperatures up to 150°C, so the inside of the FT-100 would not be any problems. The adhesive (glue) on the backside is conductive. There is another stripe from 3M that has silver mixed with the adhesive. Will of course work better, but 1181 will work just fine and is “less” expensive.
Here I show were to add some extra stripes. The 3M cupper-stripe can be solder, no problems at all. Just remember it’s a stripe – so do not fall a sleep with the iron fixed to the stripe, hi. Make the length the double and also put some over the “knee” over to the other side. Take also a look at those inside the top-cap. They could need some extra stripes or be replaced. On the big picture, I have also added the extra grounding that Yeasu does. (Red dots with small red line between). I do not think this is necessary, if you use proper stripe on the place I show on the left side. But it will not heart!
If you have to turn the card over – beware of that little green wire. Easy to break – hard to replace. You also have to loose all contacts, not just a few as written in the manual.
On the back-side of the card, there are two trailing contacts. Make sure they are really hitting the aluminium as good as they can.
Right now it is connected to a GPM-1500 (multiband vertical) 1.8 – 30MHz antenna and a LDG AT-100Pro Antenna tuner.