Evening All
My new “Overseas” manufactured 45w HF amp arrived at work today.
I bought it to use with my FT817.
The seller stated that they would supply an interface cable for keying the amp from the acc socket on the radio.
Said cable is a kit of parts with no diagram.
As I am stuck at work double shifting, can anybody help me out with a diagram for the pin outs please?
I only need to switch to TX - simple 2 wire cable.
Next trick on night shift is to make a new link dipole in the warehouse at eve meal break!
Hi Andy
Thank you.
Stuck in China at present on a short contract - No Google services at all and no Facebook for those who do (I dont!).
They have allowed me my soldering iron though…
On with the cable making it is for entertainment tonight.
73’s
Tim
Whilst there’s lots wrong with Google (like a failure to pay proper tax in the UK), an internet without Google search would be challenging. Do they not allow Bing either?
Yahoo works - kind of, but content is filtered.
Anything .com, US, European or Western is filtered, slowed down and content removed.
Internet is so monitored that the letters in this reply take about 6 seconds each to appear!
Its been a while since I did close up soldering - this old age thing is nothing to look forward to.
Looks like a trip to specsavers is in order.
Thanks Allan, I dug deeper on Ebay and found wiring instructions posted from a different seller. Also got some good advice on an 817 forum. Your photo confirms I am on the right track. Thanks again.
My MX-P50M just arrived from Hong Kong. No cables at all were included, not even a kit. Anyone have anything new to add as to where the control cable at least can be sources from? Many thanks, Neil - K6KWI
However, you will need to remove the small black plug on the back of your new linear and put on an RCA socket for the cable to work. If that is too much hassle, then you could buy this adapter:
Yes there is a little black plug on the control cable.
Matt,
Thanks for the link. I will order the cable(s) today. I was very surprised to discover it came with no cables.
I have found no supplier here in the US for parts for this amp. The amp its self is not available domestically and must be imported. Mine came from Hong Kong, I don’t know anyone else here who has one.
I hope it works as well for me as it appears to for others on YouTube etc.
You could, of course, just splice a wire from the back of the amp to a mini DIN plug. The relevant contacts are shown above. Might save you a fair bit of money.
Cheers
Matt
I have one of the amps but I bought it from another ham, don’t know if he had to assemble the keying cable. 8 pin din plugs are a bit fiddly, but you can always buy an assembled cable and adapt it with a pair of side cutters.
I experimented with the ft817 driving the amp. According to my power meter, a cross needle meter included in an ATU, the amp produces just over 40w whether it’s driven by 5w or 2.5w. This means 5w is overdriving it and will produce a wide signal on ssb. There is no ALC feedback connection to reduce the drive, and anyway those systems still produce dirty signals.
At 1w input it produced 20w and at half a watt it was about 10w. So it is apparently linear-ish at low power levels, typical of solid state amplifiers, but output flattens off with higher drive. 2.5w is probably the practical and socially acceptable drive limit for good operation.
Your amp may vary, but I recommend testing this aspect.
A fringe benefit of this outcome is that the 817 can run at a lower power level, resulting in a modest saving in battery consumption.
