KW Vanguard AM Transmitter - UK Vintage Radio Repair and Restoration Discussion Forum

gw3xjc · 6th Nov 2007, 7:27 pm

Anyone remember the KW Vanguard
gw3xjc

Station X · 6th Nov 2007, 7:39 pm

Yes. I restored one recently. I haven't tried it out on the air yet though. It's the MK2 version with a clamp valve and seems to have been fitted with the modification for top band at the factory.

Restoration was pretty straight forward. Cabinet sand blasted and powdercoated. All electrolytics and waxies changed together with out of spec resistors. A couple of valves changed I think. I had to rebuild a couple of the rotary switches. as the springy metal around the indexing balls had cracked. A couple of new SM capacitors put in the VFO before recalibrating it. Plenty of RF into a dummy load. I have a nice KW107 ATU to go with it.

I take it you have the circuit, manuals etc?

ronbryan · 6th Nov 2007, 7:49 pm

This seems like a major amount of work. Do you have any pictures of it, Graham?

Ron

Aub · 6th Nov 2007, 8:21 pm

Hi There,

If you can join in the VMARS AM net on 3.615 Mc/s, at 0830 on Saturdays, you'll probably hear Tony, G8AQN. He has just finished a complete re-build of a Vanguard, similar to Graham's efforts. I'm sure he has lots of information about the transmitter and what's involved.

73's

Aub (G4KQL)

Skywave · 6th Nov 2007, 10:29 pm

Quote:

Originally Posted by gw3xjc

Anyone remember the KW Vanguard

Certainly do!

I've got one in the "pending overhaul dep't."

It's in a very sorry state & will need a substantial amount of work - e.g. completely rewinding the PA tank coil for a start. I have the manual.

One day . . . one day . . .

Al / Skywave.

gw3xjc · 11th Nov 2007, 10:09 pm

Hi Gang, Yes all very interesting, i have the manual and all the circuits. I had it given to me about 3 years ago from an old timer who stored it in a garage without its case. BTW I still do not have a case for it. Anyway, the under chasis is immaculate. However the top of the chasis is a bit of a mess. The vanes on the vfo are shot. As luck happens a few months ago with a guy advertising this electronic bit of kit. I recognised it as a Gelosos vfo, we did the deal and i bought it for about £11 brand new. Could not believe my luck. It's a winter project i'm afraid. I have lots of other things on the go at the moment. I presume all the transformers are OK. I will have to do a bit of a search for high voltage electrolytics I presume. Having dealt with electronics all my life I was amased to find how few components there are in the Vanguard, I had forgotten. These days there seems to be everything crammed in a circuit board.

73's and thanks for all your comment, i can only manage to lookat this site about once a week at the moment.
Rog GW3XJC [email address removed]

Skywave · 13th Nov 2007, 12:01 am

Quote:

Originally Posted by gw3xjc

I presume all the transformers are OK.

Maybe yes;

maybe no

I do know of a G4 who took the precaution of storing a similarly-found Vanguard in his airing-cupboard for several weeks just to be sure that all the moisture in the transformers (and elsewhere) was driven out.

Seems like a wise precaution to me.

Al / Skywave.

real2real · 6th Feb 2008, 12:22 pm

I have one given to me years ago, it has had the original knobs replaced by rather smart spun aluminium ones. As per everyone else, replaced all the usual bits n pieces, and fitted the clamp valve. This rig was my first taste of amateur radio at a garden fete (remember those ?) about 1958, being demonstrated by I think the Reigate ATS.
I have stripped all the paint and re-done the lettering etc on the front panel.
Great rig, lovely audio..
Andy G3UEQ

6th Nov 2007, 7:27 pm	#1
gw3xjc Retired Dormant Member Join Date: Jun 2005 Location: Maesteg, Bridgend County Borough, Wales. Posts: 26	KW Vanguard AM Transmitter Anyone remember the KW Vanguard gw3xjc

6th Nov 2007, 7:39 pm	#2
Station X Moderator Join Date: Jan 2003 Location: Ipswich, Suffolk, IP4, UK. Posts: 21,289	Re: KW Vanguard AM Transmitter Yes. I restored one recently. I haven't tried it out on the air yet though. It's the MK2 version with a clamp valve and seems to have been fitted with the modification for top band at the factory. Restoration was pretty straight forward. Cabinet sand blasted and powdercoated. All electrolytics and waxies changed together with out of spec resistors. A couple of valves changed I think. I had to rebuild a couple of the rotary switches. as the springy metal around the indexing balls had cracked. A couple of new SM capacitors put in the VFO before recalibrating it. Plenty of RF into a dummy load. I have a nice KW107 ATU to go with it. I take it you have the circuit, manuals etc? __________________ Graham. Forum Moderator Reach for your meter before you reach for your soldering iron.

6th Nov 2007, 7:49 pm	#3
ronbryan Octode Join Date: Jan 2003 Location: Guildford, Surrey, UK. Posts: 1,960	Re: KW Vanguard AM Transmitter This seems like a major amount of work. Do you have any pictures of it, Graham? Ron

6th Nov 2007, 8:21 pm	#4
Aub Nonode Join Date: Mar 2005 Location: Nuneaton, Warwickshire, UK. Posts: 2,039	Re: KW Vanguard AM Transmitter Hi There, If you can join in the VMARS AM net on 3.615 Mc/s, at 0830 on Saturdays, you'll probably hear Tony, G8AQN. He has just finished a complete re-build of a Vanguard, similar to Graham's efforts. I'm sure he has lots of information about the transmitter and what's involved. 73's Aub (G4KQL)

11th Nov 2007, 10:09 pm	#6
gw3xjc Retired Dormant Member Join Date: Jun 2005 Location: Maesteg, Bridgend County Borough, Wales. Posts: 26	Re: KW Vanguard AM Transmitter Hi Gang, Yes all very interesting, i have the manual and all the circuits. I had it given to me about 3 years ago from an old timer who stored it in a garage without its case. BTW I still do not have a case for it. Anyway, the under chasis is immaculate. However the top of the chasis is a bit of a mess. The vanes on the vfo are shot. As luck happens a few months ago with a guy advertising this electronic bit of kit. I recognised it as a Gelosos vfo, we did the deal and i bought it for about £11 brand new. Could not believe my luck. It's a winter project i'm afraid. I have lots of other things on the go at the moment. I presume all the transformers are OK. I will have to do a bit of a search for high voltage electrolytics I presume. Having dealt with electronics all my life I was amased to find how few components there are in the Vanguard, I had forgotten. These days there seems to be everything crammed in a circuit board. 73's and thanks for all your comment, i can only manage to lookat this site about once a week at the moment. Rog GW3XJC [email address removed] Last edited by Paul Stenning; 12th Nov 2007 at 9:01 pm. Reason: Email address removed in accordance with forum rules

6th Feb 2008, 12:22 pm	#8
real2real Retired Dormant Member Join Date: Jul 2005 Location: Barnham, Nr Bognor Regis, West Sussex, UK. Posts: 40	Re: KW Vanguard AM Transmitter I have one given to me years ago, it has had the original knobs replaced by rather smart spun aluminium ones. As per everyone else, replaced all the usual bits n pieces, and fitted the clamp valve. This rig was my first taste of amateur radio at a garden fete (remember those ?) about 1958, being demonstrated by I think the Reigate ATS. I have stripped all the paint and re-done the lettering etc on the front panel. Great rig, lovely audio.. Andy G3UEQ