Marconi TF144H Signal Generator Problems - UK Vintage Radio Repair and Restoration Discussion Forum

vinrads · 8th Feb 2014, 1:15 pm

Hi I am having problems with the Marconi AM Signal generator Mod TF 144 .

There is no output on ranges J and K but on L there is some, low to nothing.
I am aware of the corroded wire giving problems on the LF ranges I have successfully repaired some of the other ranges new osc valve tried HT set ok LT set OK . Anyone had dealings with this model , Mick.

Radio Wrangler · 8th Feb 2014, 1:34 pm

There have been several models of TF144 sig gens. Some completely different to others, so the suffix letter is important.

David

vinrads · 8th Feb 2014, 2:56 pm

Thanks David it is a TF144H series 2. The one with the big coil turret.

vinrads · 17th Feb 2014, 5:46 pm

Still in trouble with this one, it works on the LF ranges and the high range but no output on other ranges; tried the valves the HT and LT set OK.
Anyone got a coil turret that I could borrow just to eliminate this part?

Mick.

16dibbins · 18th Feb 2014, 9:30 pm

Hi Mick

I know that provided a reply to me over the problems with my TF144 so maybe I can help out? I can't lend you the coil pack but I do have the service manual if it's any use and may be able to help with voltage readings.
After I had repaired my TF144 I found that the output did vary on some of the bands and this was fixed by adjusting the Set ALC (RV101) a little after I had replace the 5763. Maybe that could help in you case?

Let me know if I can help

Steve

vinrads · 18th Feb 2014, 11:41 pm

Hi Steve thanks for that.

As you probably gathered I am at my wits end with this; everything checks out as per manual, voltages etc.

At the moment I am waiting for a new osc valve. I did try a supposed new one but I have my suspicions. I will let you know how I get on, regards Mick.

8th Feb 2014, 1:15 pm	#1
vinrads Dekatron Join Date: Feb 2009 Location: Chesterfield, Derbyshire, UK. Posts: 3,766	Marconi TF144H Signal Generator Problems Hi I am having problems with the Marconi AM Signal generator Mod TF 144 . There is no output on ranges J and K but on L there is some, low to nothing. I am aware of the corroded wire giving problems on the LF ranges I have successfully repaired some of the other ranges new osc valve tried HT set ok LT set OK . Anyone had dealings with this model , Mick.

8th Feb 2014, 1:34 pm	#2
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,902	Re: Marconi sig gen problems There have been several models of TF144 sig gens. Some completely different to others, so the suffix letter is important. David __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

8th Feb 2014, 2:56 pm	#3
vinrads Dekatron Join Date: Feb 2009 Location: Chesterfield, Derbyshire, UK. Posts: 3,766	Re: Marconi sig gen problems Thanks David it is a TF144H series 2. The one with the big coil turret.

17th Feb 2014, 5:46 pm	#4
vinrads Dekatron Join Date: Feb 2009 Location: Chesterfield, Derbyshire, UK. Posts: 3,766	Re: Marconi TF144H Signal Generator Problems Still in trouble with this one, it works on the LF ranges and the high range but no output on other ranges; tried the valves the HT and LT set OK. Anyone got a coil turret that I could borrow just to eliminate this part? Mick.

18th Feb 2014, 9:30 pm	#5
16dibbins Triode Join Date: Jun 2004 Location: Wirral, Merseyside, UK. Posts: 42	Re: Marconi TF144H Signal Generator Problems Hi Mick I know that provided a reply to me over the problems with my TF144 so maybe I can help out? I can't lend you the coil pack but I do have the service manual if it's any use and may be able to help with voltage readings. After I had repaired my TF144 I found that the output did vary on some of the bands and this was fixed by adjusting the Set ALC (RV101) a little after I had replace the 5763. Maybe that could help in you case? Let me know if I can help Steve __________________ Steve Mc

18th Feb 2014, 11:41 pm	#6
vinrads Dekatron Join Date: Feb 2009 Location: Chesterfield, Derbyshire, UK. Posts: 3,766	Re: Marconi TF144H Signal Generator Problems Hi Steve thanks for that. As you probably gathered I am at my wits end with this; everything checks out as per manual, voltages etc. At the moment I am waiting for a new osc valve. I did try a supposed new one but I have my suspicions. I will let you know how I get on, regards Mick. Last edited by Mike Phelan; 19th Feb 2014 at 9:42 am.