Racal RA17 - Info/advice wanted. - UK Vintage Radio Repair and Restoration Discussion Forum

John GW0OAJ · 21st Dec 2009, 11:29 pm

In connection with this thread......

It would be nice if someone had a consolidated, late stage list of the mod state of the Mk II / III sets - and even better, copies of the mod leaflets. I would be very grateful for any advice on that, rather than just the manual and cct diagrams that I have.

My first snag - rather than go for a dubious refurbish of the shonky AF / IF gain pots (last resort), does anyone know of a source of NoS Colvern WW pots? Where did they all go to? They were 10 a penny then and we did not want them - we wanted the miniature, Gucci, cermet track jobs that are all you get now. When you want a mans pot for a real job....... bah, don't go there.......

cmjones01 · 22nd Dec 2009, 2:44 pm

I don't know anything about RA17 mods, but Colvern pots are still available from Farnell as far as I can see. Both the 1W CLR1106 series (small black ones) and 3W CLR4001 series (big ones with the red back) are listed. Their website is offline at the moment but a search for those type codes should dig them up.

g4aaw pete · 22nd Dec 2009, 7:11 pm

Hi John

There are various RA17 manuals at
http://kilocycles.co.uk/uk-commonwealth-rx-tx.html
and descriptions of variants at
http://www.recelectronics.demon.co.uk/ra17.htm

hope this will answer some questions

Regards
Pete

John GW0OAJ · 8th Jan 2010, 9:03 pm

Belated thanks, chaps.

I was aware of those links, but thank you. Already having a Farnell account, I had searched them for suitable pots. I can't get exactly what I want, but I will get something that will do.

John

amornummi · 5th Jul 2010, 12:19 am

Noisy AF gain pot can be cured by putting 1 meg resistor af amp grid to ground, then feed from pot wiper via 0.1 mf.
Another useful trick , to double audio out is to parallel the two audio o/p valves, simply dis the existing wire to V23 grid. Join V23 grid to pin 1 V22. Then connect a 0.47 mf between the two anodes.

saxmaniac · 8th Jul 2010, 2:50 pm

I can send you a pdf of a manual if you want, just give me your direct email

21st Dec 2009, 11:29 pm	#1
John GW0OAJ Diode Join Date: Sep 2009 Location: Newport, South Wales, UK. Posts: 3	Racal RA17 - Info/advice wanted. In connection with this thread...... It would be nice if someone had a consolidated, late stage list of the mod state of the Mk II / III sets - and even better, copies of the mod leaflets. I would be very grateful for any advice on that, rather than just the manual and cct diagrams that I have. My first snag - rather than go for a dubious refurbish of the shonky AF / IF gain pots (last resort), does anyone know of a source of NoS Colvern WW pots? Where did they all go to? They were 10 a penny then and we did not want them - we wanted the miniature, Gucci, cermet track jobs that are all you get now. When you want a mans pot for a real job....... bah, don't go there....... Attached Thumbnails Last edited by Darren-UK; 22nd Dec 2009 at 12:40 am. Reason: Condensed down to the point.

22nd Dec 2009, 2:44 pm	#2
cmjones01 Nonode Join Date: Oct 2008 Location: Warsaw, Poland and Cambridge, UK Posts: 2,679	Re: Racal RA17 - Info/advice wanted. I don't know anything about RA17 mods, but Colvern pots are still available from Farnell as far as I can see. Both the 1W CLR1106 series (small black ones) and 3W CLR4001 series (big ones with the red back) are listed. Their website is offline at the moment but a search for those type codes should dig them up.

22nd Dec 2009, 7:11 pm	#3
g4aaw pete Heptode Join Date: Jan 2008 Location: Birchington Kent, UK. Posts: 596	Re: Racal RA17 - Info/advice wanted. Hi John There are various RA17 manuals at http://kilocycles.co.uk/uk-commonwealth-rx-tx.html and descriptions of variants at http://www.recelectronics.demon.co.uk/ra17.htm hope this will answer some questions Regards Pete

8th Jan 2010, 9:03 pm	#4
John GW0OAJ Diode Join Date: Sep 2009 Location: Newport, South Wales, UK. Posts: 3	Re: Racal RA17 - Info/advice wanted. Belated thanks, chaps. I was aware of those links, but thank you. Already having a Farnell account, I had searched them for suitable pots. I can't get exactly what I want, but I will get something that will do. John

5th Jul 2010, 12:19 am	#5
amornummi Triode Join Date: Mar 2008 Location: Huddersfield, West Yorkshire, UK. Posts: 45	Re: Racal RA17 - Info/advice wanted. Noisy AF gain pot can be cured by putting 1 meg resistor af amp grid to ground, then feed from pot wiper via 0.1 mf. Another useful trick , to double audio out is to parallel the two audio o/p valves, simply dis the existing wire to V23 grid. Join V23 grid to pin 1 V22. Then connect a 0.47 mf between the two anodes.

8th Jul 2010, 2:50 pm	#6
saxmaniac Heptode Join Date: Oct 2007 Location: Birmingham, West Midlands, UK. Posts: 618	Re: Racal RA17 - Info/advice wanted. I can send you a pdf of a manual if you want, just give me your direct email