Tokyo Hy-Power HL-110V Repairs

Switch replacement and testing

2m
construction
Author

Alex Johnstone

Published

May 9, 2025

Tokyo Hy-Power HL-110V

Tokyo Hy-Power HL-110V

Quite a while ago I bought this 2m amp to use with my ICOM IC-705. It’s a 110W amp that can be driven by either 10W or 2W, and lots of details and references can be found on RigPix database. I thought that I could use it at home as my 2m base station, or even take it with me to do some SSB with a bit more than the 10W of the 705 (with external battery). The portable part was quickly dismissed when I realised how heavy it actually is - circa 2.5 kg. However, I had ideas of having the 705 in the office, and then a 2m and a HF amp in the garage and I could do everything from the 705. In the end I just put the ftdx10 in the office and realised it wasn’t that big and did everything I need without having to buy a HF amp and figure out how to manage that semi-remotely. Anyway, the first time I came to use the amp the power level switch broke when I moved it. The rod seemed to come loose internal to the switch and did nothing. Having not tested it yet I didn’t want to try until I replaced it in case the switch had failed in a strange way. I opened it up to have a look inside and thought I should replace the switch. This was all quite a while ago and for various reasons (laziness) I did nothing about it. After a shack tidy and sort out recently, I decided I would finally fix it and looked to order a replacement switch online.

Make your own jokes

Make your own jokes

Unfortunately, I couldn’t find any DPDT switches of the 6A rating with a long lever - cue someone immediately emailing me with a link to 1,000s for 20p each - and so ended up with just a regular length one. Amp repairs is maybe slightly aspirational for what is really just unsoldering and resoldering a switch. It was a bit fiddly to get in and out as I didn’t want to dismantle the amp more than necessary.

The old switch at the top

The old switch at the top

Unsoldering did seem to release 1970s smells but nothing was amiss, I did catch the side of the resistors with the soldering iron but no harm done. I could’ve done with a tiny spanner to loosen the nuts on either side of the panel but managed with a pair of pliers.

Connections on the switch

Connections on the switch

There’s also a circle of black felt that goes between the front panel and the supporting panel, which blacks out the holes at the front, so it looks good. A nice touch, but also fiddly to get back into place. I soldered some wire across the top two pins first and then mounted it back into the case. I used some tweezers to hold the wires and resistors in place whilst I soldered them back to the switch.

New switch in place

New switch in place

I used a multimeter to check continuity just to make sure I hadn’t soldered extra parts together as it was a little tricky to see, and all seemed good, so time to power it on!

ft-857 driver and power meter

ft-857 driver and power meter

This would be the first time actually testing it, and I fitted some Power Pole adapters to it as well. First I was going to try with 10W and see what I got out, and it was just over 110W. The power meter on the amp and my Avair one matched up well too.

10W in; 110W out

10W in; 110W out

100/110W out on its own meter

100/110W out on its own meter

Next was to try with 2W. There’s a little switch on the back of the amp that you have to set. It also has a screwed on plate, so if you only wanted to use it with 2W or 10W you can screw that on and stop the switch from being changed.

Back of amp, input power switch on the left

Back of amp, input power switch on the left

Unfortunately, the ft-857 only goes down to 5W, and so I was probably slightly over driving it. However, 2W would be ideal for the 705 or even a HT. At 2W the amp uses two stages of amplification but still yields 110W, or in my case with 5W driver, 130W out.

5W in; 130W out

5W in; 130W out

Higher than before, although doesn’t show 130W. I only tested it at 5W for a few seconds to take a couple of photos.

Higher than before, although doesn’t show 130W. I only tested it at 5W for a few seconds to take a couple of photos.

So a success! Which is good, as the ebay auction was a long time ago now 😅. The question is, what do I do with it now? I’ve sold my 705 as I never used it and bought the ft857 for higher power 2m SSB and HF for SOTA. The 857 “only” does 50W of VHF, but that’s plenty on a summit with a yagi, I just wanted a little more than 10W, and probably 20-30W is sufficient. At home I have a FM only rig for 2m for the occasional SOTA chase or brief chat with the locals, and that does 50W. I have dreams of doing something fancy like 2m EME, but then I’d probably want 300+W. I’m thinking it doesn’t really have a use, and so should I sell it. At least the buyer can see it works. These Tokyo amps are lovely quality, but is it just going to sit in a cupboard for ever more?

It was fun to fix it, even if the fix was tiny.

If you have any comments or questions, please send me an email.