FT221, it was one of those days.... - UK Vintage Radio Repair and Restoration Discussion Forum

sidspop · 21st Feb 2022, 3:06 am

I have 3 of these radios. Not quite sure why I have three, I can only talk on one at a time. Possibly because it was the first decent 2 metre set I ever owned. I had an FDK Multi 2000 before it, but that was only any good for a wheelchock if my handbrake cable broke.
I bought one years ago, all the caps need replacing. Not because of some "re-cap it" American type bull. The ceramic caps are all split physically, I have not got around to doing it yet.
I got given another by a local, bought off a car boot sale, but he could not use it as it's not digital. The third one I got given for aligning a CB.
The good news is they are all Muteked.
Yesterday I looked at one with very low RF output, about 100mW. Checked levels, checked voltages, seemed low to exciter. I compared to working unit, and then swapped exciter boards.
As expected, the good exciter worked in the duff rig. Then the duff exciter worked in the good rig. I can only presume dirty contacts for the exciter board.
It passed the time.
I then noticed FM RF out was about 10 watts. By moving the mode switch carefully that became 15. Dirty switch. It looks easy, but stripping the switch in situ is a pain, two wires have to be removed, and all contacts cleaned with IPA, fibreglass pencil and cotton buds. Looking at the state of the buds, I would guess it had WD40 previously.
So the moral of the story is sometimes it's an easy fix, and sometimes we dig far too deep to fix a problem.
Now all I have to do is find out why my 225 does not TX in SSB, but that's another job.
Anybody know what the chassis mount pot is numbered, and purpose? The one buried between two boards at rear.

Andrew2 · 21st Feb 2022, 9:32 am

'but he could not use it as it's not digital...'

May the Lord help us.

murphyv310 · 21st Feb 2022, 1:22 pm

Quote:

Originally Posted by Andrew2

'but he could not use it as it's not digital...'

May the Lord help us.

Wonderful. I have to agree

AdrianH · 21st Feb 2022, 1:56 pm

I spent a few hours stripping down the front of my FT-902DM so that I could access the attenuation switch and clean it out with cotton buds and servisol. Works well now and no screws left over at the end which is a bonus. Just found out that my wire dipole has water in the co-ax. I prefer the older radios and probably despise digital, but that's me.

Keep the old gear going, reduce the FM mod for 12.5KHz bandwidth, think that is what it is meant to be now (+/-2.5KHz peak).

Adrian

PA3DAF, Erwin · 1st Apr 2022, 10:03 pm

Quote:

Originally Posted by sidspop

Anybody know what the chassis mount pot is numbered, and purpose? The one buried between two boards at rear.

Yes, It's VR09. It's between the exciter and booster unit in the schematic. This adjusts the maximum carrier level on FM.

I recently bought a FT225RD and spent a couple of hours reading the user manual and schematics and found that there are several pots and trimmers which are not mentioned in the user manual.

Cheers

Erwin, PA3DAF

21st Feb 2022, 3:06 am	#1
sidspop Triode Join Date: Jun 2015 Location: West Bromwich, West Midlands, UK. Posts: 42	FT221, it was one of those days.... I have 3 of these radios. Not quite sure why I have three, I can only talk on one at a time. Possibly because it was the first decent 2 metre set I ever owned. I had an FDK Multi 2000 before it, but that was only any good for a wheelchock if my handbrake cable broke. I bought one years ago, all the caps need replacing. Not because of some "re-cap it" American type bull. The ceramic caps are all split physically, I have not got around to doing it yet. I got given another by a local, bought off a car boot sale, but he could not use it as it's not digital. The third one I got given for aligning a CB. The good news is they are all Muteked. Yesterday I looked at one with very low RF output, about 100mW. Checked levels, checked voltages, seemed low to exciter. I compared to working unit, and then swapped exciter boards. As expected, the good exciter worked in the duff rig. Then the duff exciter worked in the good rig. I can only presume dirty contacts for the exciter board. It passed the time. I then noticed FM RF out was about 10 watts. By moving the mode switch carefully that became 15. Dirty switch. It looks easy, but stripping the switch in situ is a pain, two wires have to be removed, and all contacts cleaned with IPA, fibreglass pencil and cotton buds. Looking at the state of the buds, I would guess it had WD40 previously. So the moral of the story is sometimes it's an easy fix, and sometimes we dig far too deep to fix a problem. Now all I have to do is find out why my 225 does not TX in SSB, but that's another job. Anybody know what the chassis mount pot is numbered, and purpose? The one buried between two boards at rear.

21st Feb 2022, 9:32 am	#2
Andrew2 Nonode Join Date: Mar 2010 Location: Dukinfield, Cheshire, UK. Posts: 2,038	Re: FT221, it was one of those days.... 'but he could not use it as it's not digital...' May the Lord help us. __________________ Andy G1HBE.

21st Feb 2022, 1:56 pm	#4
AdrianH Octode Join Date: Mar 2020 Location: Blackburn with Darwen, Lancashire, UK. Posts: 1,573	Re: FT221, it was one of those days.... I spent a few hours stripping down the front of my FT-902DM so that I could access the attenuation switch and clean it out with cotton buds and servisol. Works well now and no screws left over at the end which is a bonus. Just found out that my wire dipole has water in the co-ax. I prefer the older radios and probably despise digital, but that's me. Keep the old gear going, reduce the FM mod for 12.5KHz bandwidth, think that is what it is meant to be now (+/-2.5KHz peak). Adrian __________________ Asking questions and learning, or trying to! Youtube EF91Valve