Pye v4 - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

beltinge bore · 5th Nov 2013, 6:25 pm

Hello again

Had a little trip to Cornwall & spent a some time with young Stephen (FREYA) I came back with a set of PYE scan coils. (thanks Stephen). These have been fitted after a struggle. The leads had been cut close to the coils. This produced a very faint raster with lots of frame cramp & no sync. Ion trap was manipulated slowly & improved things slightly.

After some more cap changing I got line sync OK.

I replaced the band 111 tuner & connected the Aurora which gave me a week test card with no frame hold & upside down (this little problem had eluded me as I was using a mirror to view the screen!) Swapping the frame coil tags over cured this. After more cap changes the frame linearity improved but still no hold.

The frame hold pot was O/C and signs of dodgy soldering around it this was repalced. I now have frame hold bags of height & good linearity.Carried on re-capping & now all controls (except spot limiter) function as normal. The picture is now quite bright with good contrast. The sound is perfect.

My problem is lack of width (about an inch either side) & the picture balloons & disappears as the brightness control is advanced. I have changed the EY51 & tried new PL81& PY81 with no improvement. There is a strong spark at both ends of the EY51 but its heater is not very bright. Tube heater volts now measure 5.8v. The LOPT winding's don't seem to be getting warm. HT1 reads 200v HT2 reads 165v.

The set has been very damp as the scan coils were a real mess. Any advice would be very welcome.

Regards and thanks Steve

P.S. I stayed for the auction at BVWS Harpenden & couldn't resist bidding on another V4. This only needed a methodical re-cap, a couple of resistors & a contrast pot. It has a great tube & the cabinet has spruced up well so after a 50 year wait I have a working V4! I don't want to be beaten by the first one though!!

Freya · 18th Nov 2013, 10:08 am

Have you made any further progress, glad to see the coils were ok.

beltinge bore · 19th Nov 2013, 12:09 am

Hello Stephen & all
Hope all is is well in Kernow. I carried on with this. Width is now almost OK. Looks like a H/C problem with the tube. Tapping the neck gives a great picture & heater volts climb to 6.2v. Have tipped set on its face & repeated the above & now have a nice bright picture. How long this will last remains to be seen.
My other V4 is really nice so I at least have one good at last. I have a spare tube (condition unknown) kindly donated by Peter in Seaford so this is an option.
My current little project is an Ekco TMB272 which I thought would be easier than a V4. 3 weeks later I'm not so sure!!! (I will try to add some pictures & a write up later)
Regards Steve.

5th Nov 2013, 6:25 pm	#21
beltinge bore Pentode Join Date: Dec 2012 Location: Herne Bay, Kent, UK. Posts: 233	Re: Pye v4 Hello again Had a little trip to Cornwall & spent a some time with young Stephen (FREYA) I came back with a set of PYE scan coils. (thanks Stephen). These have been fitted after a struggle. The leads had been cut close to the coils. This produced a very faint raster with lots of frame cramp & no sync. Ion trap was manipulated slowly & improved things slightly. After some more cap changing I got line sync OK. I replaced the band 111 tuner & connected the Aurora which gave me a week test card with no frame hold & upside down (this little problem had eluded me as I was using a mirror to view the screen!) Swapping the frame coil tags over cured this. After more cap changes the frame linearity improved but still no hold. The frame hold pot was O/C and signs of dodgy soldering around it this was repalced. I now have frame hold bags of height & good linearity.Carried on re-capping & now all controls (except spot limiter) function as normal. The picture is now quite bright with good contrast. The sound is perfect. My problem is lack of width (about an inch either side) & the picture balloons & disappears as the brightness control is advanced. I have changed the EY51 & tried new PL81& PY81 with no improvement. There is a strong spark at both ends of the EY51 but its heater is not very bright. Tube heater volts now measure 5.8v. The LOPT winding's don't seem to be getting warm. HT1 reads 200v HT2 reads 165v. The set has been very damp as the scan coils were a real mess. Any advice would be very welcome. Regards and thanks Steve P.S. I stayed for the auction at BVWS Harpenden & couldn't resist bidding on another V4. This only needed a methodical re-cap, a couple of resistors & a contrast pot. It has a great tube & the cabinet has spruced up well so after a 50 year wait I have a working V4! I don't want to be beaten by the first one though!!

18th Nov 2013, 10:08 am	#22
Freya Octode Join Date: Jan 2009 Location: Falmouth, Cornwall, UK. Posts: 1,991	Re: Pye v4 Have you made any further progress, glad to see the coils were ok. __________________ Stephen _________"It`s only an old telly" ___

19th Nov 2013, 12:09 am	#23
beltinge bore Pentode Join Date: Dec 2012 Location: Herne Bay, Kent, UK. Posts: 233	Re: Pye v4 Hello Stephen & all Hope all is is well in Kernow. I carried on with this. Width is now almost OK. Looks like a H/C problem with the tube. Tapping the neck gives a great picture & heater volts climb to 6.2v. Have tipped set on its face & repeated the above & now have a nice bright picture. How long this will last remains to be seen. My other V4 is really nice so I at least have one good at last. I have a spare tube (condition unknown) kindly donated by Peter in Seaford so this is an option. My current little project is an Ekco TMB272 which I thought would be easier than a V4. 3 weeks later I'm not so sure!!! (I will try to add some pictures & a write up later) Regards Steve.