Pye CTL58F. - UK Vintage Radio Repair and Restoration Discussion Forum

FERNSEH · 23rd Oct 2013, 4:40 pm

One the sets I picked up from Wales fourteen days ago. Doesn't time fly?

This set is a Pye CTL58F, a derivitive of the much earlier CW17 series.
A full spec receiver with flywheel line sync, three stage vision and sound IF amplifiers, twin 'speakers and employs an early frame grid valve in the tuner, the PCC88.
Standard HKS test procedure, just plug it in. As you can see from the attached picture, something already on the screen.
Well it's a start.
I used to service quite a few of these sets in the old days.
There was a version with FM radio, the CTL58VS. This set did not employ a Pye made tuner, a Cyldon type C if my memory serves me well.

DFWB.

FERNSEH · 23rd Oct 2013, 4:58 pm

Employing a very similar chassis as the CTL58F is this ugly PAM model 501F.
Big brown box cabinet and even so they've fitted it with a 90 degree CRT, the rare Mullard MW43-80.

DFWB.

Heatercathodeshort · 23rd Oct 2013, 7:15 pm

The CTL will be a very interesting restoration David. It's one of the few 405 line receivers that actually produces a 'hiss' on sound and screen noise when not supplied with a signal. I believe it won an award in 1958 presented by the Design Council.
Great first light! Looks an easy one.
The Pam looks a bit boring but being yet another fringe chassis and a very early printed circuit model, it must be a very similar receiver to the CTL58F but in a Cinderella frock.
Amazing number of PAM receivers around. I have only seen one JENNIFER. Regards, John.

Tazman1966 · 23rd Oct 2013, 8:38 pm

Jennifer

FERNSEH · 24th Oct 2013, 1:22 am

Hi John, I haven't come across a Jennifer before, a Kuba Florence though.
The CTL58 employs the best mono CRT ever, the AW43-80. Except this one isn't. It has that old Mullard problem, a partially shorted heater. Only 3 volts can be measured at pins 1 and 12.
I have a NOS AW43-80Z upstairs. It was always my intention to fit this tube into what we would say is a worthy set. Does the CTL58F qualify?

About the AW43-80Z. This tube is a direct replacement for the AW43-80.
It has a similar gun assembly as the 110 degree AW43-88 and so it has the B8H base instead of the twelve pin B12A. No ion trap. 38mm neck like the AW43-80.

DFWB.

Heatercathodeshort · 24th Oct 2013, 8:55 am

I remember the AW43-80Z. The gun assembly was also fitted into the MW43-69Z but I can't remember if the original focus magnet was retained.
Yes David, the CTL must be a worthy contender for your tube and keeping a posh frock in the wardrobe 'in case it gets dirty' is something I am also guilty of!
Amazing how many of those Mullard tubes have the partial heater short problem. Even Mazda tubes with all their problems, did not suffer that particular heater fault. It was a basic design error and like Mazda's heater cathode short problem, should have been dealt with a lot earlier.
That first light is very encouraging, at least the LOPT and most of the circuitry will be restorable. I would leave the tube change untill you have completed all the work. We don't want any popped necks...John.

Brigham · 24th Oct 2013, 7:17 pm

Quote:

Originally Posted by Heatercathodeshort

The CTL will be a very interesting restoration David. It's one of the few 405 line receivers that actually produces a 'hiss' on sound and screen noise when not supplied with a signal. I believe it won an award in 1958 presented by the Design Council.
Great first light! Looks an easy one.
The Pam looks a bit boring but being yet another fringe chassis and a very early printed circuit model, it must be a very similar receiver to the CTL58F but in a Cinderella frock.
Amazing number of PAM receivers around. I have only seen one JENNIFER. Regards, John.

The Model CS17 certainly won a Design Council award for top designer Robin Day. It was the 'Contemporary' version, the CTM17 being the 'Continental'.

FERNSEH · 24th Oct 2013, 8:03 pm

There is a CS17 upstairs. An electrical restoration was done way back in the nineties but cabinet has a printed woodgrain effect which is in poor order.
I have a CTM17S, the Pye Continental. Unlike the CTL58, CW17 and the Pam 501F this set has the very basic 17-21S chassis.

DFWB.

FERNSEH · 25th Oct 2013, 5:37 pm

I've removed the chassis from the cabinet, not an easy job as one of the securing screws had seized. Some rough engineering practises needed to to remove it.
it came as a surprise to find that the chassis and CRT came out as one unit.
I was expecting this set to similar to the CW17 series in which the CRT is mounted separately in the cabinet.
It more than forty-five years since I have worked on a CTL58.

DFWB.

FERNSEH · 28th Oct 2013, 5:29 pm

The line output transformer has failed. There is a tiny spark at the anode of the PL36 and an equally small spark at the anode of the EY86 EHT rectifier.
There is 60 volts peak to peak drive sawtooth drive to the control grid of the PL36. I'd reckon that's about right. The coupling capacitor C101 (0.01microfarads) was leaky and so it was changed. Same with the boost capacitor.

DFWB.

FERNSEH · 28th Oct 2013, 7:08 pm

I've hooked up another line output transformer and now there is a healthy spark at the cap of the EHT rectifier valve so that proves the original LOPTx is faulty. The scan scan coils are not yet connected.

The transformer I'm using was donated by Wilfrid (wiwior) It's a transformer that has been proven to work on all three line standards, 405, 625 and 819.

FERNSEH · 11th Apr 2015, 11:31 am

Thanks to JohnHKS the Pye CTL58 might well be saved. One of the items I took away this week from John's place was a rusty RGD Deep 17 chassis.
There is no way this poor wretched thing will ever be restored but it's parts could be transplanted into the Pye. That AW43-80 tube might be perfect, anything could be better than the CRT that's presently in the Pye. The RGD line output transformer is of a similar design as the Pye, so that part could go in, but not straight away of course. John recommends passing a small current through the overwind, just sufficient to warm it up to drive out any moisture. Start off with say 50mA.

The Pye was about to get the chop but now there's a chance it could be saved. Let's find out if it can.

DFWB.

FERNSEH · 11th Apr 2015, 8:38 pm

The AW43-80 CRT has been removed from the RGD and fitted into the Pye CTL58. It's perfect! Lots of brightness after the valves have warmed up, but then after a few minutes the sides of the raster come in. It's likely the substitute line output transformer is faulty. If the line output stage can be sorted out this will be a very good set.
Made in mid 1958 this Pye receiver is one of the first sets to employ the Mullard PCC89 frame grid RF amplifier valve. Earlier Pye sets employed the PCC88 in the tuner. Both these valves are a huge improvement over the much earlier PCC84.

DFWB.

FERNSEH · 12th Apr 2015, 6:40 pm

After allowing the set to run some considerable time the width came out again, this is with Wilfrid's "universal" line output transformer. These transformers were designed for 819 line scanning. However, we've discovered they will work in 405 and 625 line sets.
Nevertheless, there is still not sufficient width and the EHT is only 11.5KV so I reckon the RGD Deep LOPTx is going to be the best substitute transformer for this set. The HT line measures 194 volts, that's the correct figure for this set. Boost volts is 520V.

DFWB.

Colourstar · 13th Apr 2015, 2:18 pm

Well played David. That looks a nice punchy picture, although I know the photography can flatter these things! Plenty of contrast and definition anyway.

Well done on an ingenious solution, even if it's not quite done the trick. At least you've proved what can be achieved with a bit of lateral thinking.

By the way is the sound on this set noticeably better with that two-speaker set-up? How hi is the fi?!

Steve

FERNSEH · 13th Apr 2015, 3:18 pm

Hi Steve,
Even with the low EHT of 11.5KV the picture is very bright. Imagine what it will be like if the EHT can be raised to the correct figure of 16KV.
The sound quality from this set is very good even though the output valve is the very modest PCL83. Along with the two side mounted speakers there is a small one to take care of the higher frequencies. No crossover network though.
So my next task is to remove the line output transformer from the RGD chassis, pass some current through it to warm up the windings which will drive out any moisture, then later on try the transformer in this set.
I reckon the French transformer was made for sets with 70 degree CRTs. 11KV will be fine for a 14" rectangular CRT.

DFWB.

23rd Oct 2013, 4:40 pm	#1
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Pye CTL58F. One the sets I picked up from Wales fourteen days ago. Doesn't time fly? This set is a Pye CTL58F, a derivitive of the much earlier CW17 series. A full spec receiver with flywheel line sync, three stage vision and sound IF amplifiers, twin 'speakers and employs an early frame grid valve in the tuner, the PCC88. Standard HKS test procedure, just plug it in. As you can see from the attached picture, something already on the screen. Well it's a start. I used to service quite a few of these sets in the old days. There was a version with FM radio, the CTL58VS. This set did not employ a Pye made tuner, a Cyldon type C if my memory serves me well. DFWB. Attached Thumbnails

23rd Oct 2013, 4:58 pm	#2
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Pye CTL58F. Employing a very similar chassis as the CTL58F is this ugly PAM model 501F. Big brown box cabinet and even so they've fitted it with a 90 degree CRT, the rare Mullard MW43-80. DFWB. Attached Thumbnails

23rd Oct 2013, 7:15 pm	#3
Heatercathodeshort Dekatron Join Date: Jun 2005 Location: Warnham, West Sussex. 10 miles south of DORKING. Posts: 9,147	Re: Pye CTL58F. The CTL will be a very interesting restoration David. It's one of the few 405 line receivers that actually produces a 'hiss' on sound and screen noise when not supplied with a signal. I believe it won an award in 1958 presented by the Design Council. Great first light! Looks an easy one. The Pam looks a bit boring but being yet another fringe chassis and a very early printed circuit model, it must be a very similar receiver to the CTL58F but in a Cinderella frock. Amazing number of PAM receivers around. I have only seen one JENNIFER. Regards, John.

23rd Oct 2013, 8:38 pm	#4
Tazman1966 Nonode Join Date: May 2006 Location: St Albans, Herts, UK. Posts: 2,193	Re: Pye CTL58F. Jennifer __________________ All the very best, Tas

24th Oct 2013, 1:22 am	#5
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Pye CTL58F. Hi John, I haven't come across a Jennifer before, a Kuba Florence though. The CTL58 employs the best mono CRT ever, the AW43-80. Except this one isn't. It has that old Mullard problem, a partially shorted heater. Only 3 volts can be measured at pins 1 and 12. I have a NOS AW43-80Z upstairs. It was always my intention to fit this tube into what we would say is a worthy set. Does the CTL58F qualify? About the AW43-80Z. This tube is a direct replacement for the AW43-80. It has a similar gun assembly as the 110 degree AW43-88 and so it has the B8H base instead of the twelve pin B12A. No ion trap. 38mm neck like the AW43-80. DFWB.

24th Oct 2013, 8:55 am	#6
Heatercathodeshort Dekatron Join Date: Jun 2005 Location: Warnham, West Sussex. 10 miles south of DORKING. Posts: 9,147	Re: Pye CTL58F. I remember the AW43-80Z. The gun assembly was also fitted into the MW43-69Z but I can't remember if the original focus magnet was retained. Yes David, the CTL must be a worthy contender for your tube and keeping a posh frock in the wardrobe 'in case it gets dirty' is something I am also guilty of! Amazing how many of those Mullard tubes have the partial heater short problem. Even Mazda tubes with all their problems, did not suffer that particular heater fault. It was a basic design error and like Mazda's heater cathode short problem, should have been dealt with a lot earlier. That first light is very encouraging, at least the LOPT and most of the circuitry will be restorable. I would leave the tube change untill you have completed all the work. We don't want any popped necks...John.

24th Oct 2013, 8:03 pm	#8
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Pye CTL58F. There is a CS17 upstairs. An electrical restoration was done way back in the nineties but cabinet has a printed woodgrain effect which is in poor order. I have a CTM17S, the Pye Continental. Unlike the CTL58, CW17 and the Pam 501F this set has the very basic 17-21S chassis. DFWB.

25th Oct 2013, 5:37 pm	#9
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Pye CTL58F. I've removed the chassis from the cabinet, not an easy job as one of the securing screws had seized. Some rough engineering practises needed to to remove it. it came as a surprise to find that the chassis and CRT came out as one unit. I was expecting this set to similar to the CW17 series in which the CRT is mounted separately in the cabinet. It more than forty-five years since I have worked on a CTL58. DFWB. Attached Thumbnails

28th Oct 2013, 5:29 pm	#10
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Pye CTL58F. The line output transformer has failed. There is a tiny spark at the anode of the PL36 and an equally small spark at the anode of the EY86 EHT rectifier. There is 60 volts peak to peak drive sawtooth drive to the control grid of the PL36. I'd reckon that's about right. The coupling capacitor C101 (0.01microfarads) was leaky and so it was changed. Same with the boost capacitor. DFWB. Attached Thumbnails

28th Oct 2013, 7:08 pm	#11
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Pye CTL58F. I've hooked up another line output transformer and now there is a healthy spark at the cap of the EHT rectifier valve so that proves the original LOPTx is faulty. The scan scan coils are not yet connected. The transformer I'm using was donated by Wilfrid (wiwior) It's a transformer that has been proven to work on all three line standards, 405, 625 and 819. Attached Thumbnails

11th Apr 2015, 11:31 am	#12
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Pye CTL58F. Thanks to JohnHKS the Pye CTL58 might well be saved. One of the items I took away this week from John's place was a rusty RGD Deep 17 chassis. There is no way this poor wretched thing will ever be restored but it's parts could be transplanted into the Pye. That AW43-80 tube might be perfect, anything could be better than the CRT that's presently in the Pye. The RGD line output transformer is of a similar design as the Pye, so that part could go in, but not straight away of course. John recommends passing a small current through the overwind, just sufficient to warm it up to drive out any moisture. Start off with say 50mA. The Pye was about to get the chop but now there's a chance it could be saved. Let's find out if it can. DFWB. Attached Thumbnails

11th Apr 2015, 8:38 pm	#13
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Pye CTL58F. The AW43-80 CRT has been removed from the RGD and fitted into the Pye CTL58. It's perfect! Lots of brightness after the valves have warmed up, but then after a few minutes the sides of the raster come in. It's likely the substitute line output transformer is faulty. If the line output stage can be sorted out this will be a very good set. Made in mid 1958 this Pye receiver is one of the first sets to employ the Mullard PCC89 frame grid RF amplifier valve. Earlier Pye sets employed the PCC88 in the tuner. Both these valves are a huge improvement over the much earlier PCC84. DFWB. Attached Thumbnails

12th Apr 2015, 6:40 pm	#14
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Pye CTL58F. After allowing the set to run some considerable time the width came out again, this is with Wilfrid's "universal" line output transformer. These transformers were designed for 819 line scanning. However, we've discovered they will work in 405 and 625 line sets. Nevertheless, there is still not sufficient width and the EHT is only 11.5KV so I reckon the RGD Deep LOPTx is going to be the best substitute transformer for this set. The HT line measures 194 volts, that's the correct figure for this set. Boost volts is 520V. DFWB. Attached Thumbnails

13th Apr 2015, 2:18 pm	#15
Colourstar Octode Join Date: Feb 2006 Location: Ilkeston, Derbyshire, UK. Posts: 1,397	Re: Pye CTL58F. Well played David. That looks a nice punchy picture, although I know the photography can flatter these things! Plenty of contrast and definition anyway. Well done on an ingenious solution, even if it's not quite done the trick. At least you've proved what can be achieved with a bit of lateral thinking. By the way is the sound on this set noticeably better with that two-speaker set-up? How hi is the fi?! Steve

13th Apr 2015, 3:18 pm	#16
FERNSEH Dekatron Join Date: Mar 2005 Location: Gateshead, Tyne and Wear, UK. Posts: 7,444	Re: Pye CTL58F. Hi Steve, Even with the low EHT of 11.5KV the picture is very bright. Imagine what it will be like if the EHT can be raised to the correct figure of 16KV. The sound quality from this set is very good even though the output valve is the very modest PCL83. Along with the two side mounted speakers there is a small one to take care of the higher frequencies. No crossover network though. So my next task is to remove the line output transformer from the RGD chassis, pass some current through it to warm up the windings which will drive out any moisture, then later on try the transformer in this set. I reckon the French transformer was made for sets with 70 degree CRTs. 11KV will be fine for a 14" rectangular CRT. DFWB.