Sony TV-110UK - UK Vintage Radio Repair and Restoration Discussion Forum

Studio263 · 18th Mar 2013, 8:55 am

Forum member Heater-Cathode Short gave me this set at the weekend, I’ve been after a decent one for some time now but something that was once seemingly commonplace seems to have vanished from view of late, or maybe it’s just me…

The Sony TV-110UK was introduced in 1971, at around the same time as the smaller TV-720UK, to broaden Sony’s UK range of monochrome portables. Neither of these sets replaced the well-known TV9-90UB, which continued to be available for those who required dual standard operation or the reliability of VHF reception. The TV-110UK was a larger set than had been offered in the range before, being an 11” model with a 90 degree tube. Compared to the TV9-90UB, the TV-110UK had more of a “big set” specification with proper line-gated AGC (at last!), increased boost HT supply for the video output stage, a generous 6 transistor audio section and electronic filtering for the AC power supply. The latter replaced the traditional choke filter which the previous models had used in conjunction with two large (4000uF) electrolytic capacitors with a much smaller capacitor and a simple one transistor circuit. Early issues of the circuit diagram show this drawn as part of the audio amplifier which can cause confusion; in fact the circuit is connected to the negative side of the selenium bridge rectifier. Some things didn’t change though; the frame timebase for example was almost unaltered from that used in the TV9-306UB of 1965.

The design was updated in 1973 (along with the TV9-90UB) to meet BEAB requirements. The changes included revised power switching arrangements and a sprinkling of extra fuses, in the end no less than six were fitted, four of which were 200mA types feeding individual circuit stages. Other changes made at the same time included a new audio panel with a simplified 4 transistor circuit, a simplification which made room for a silicon bridge rectifier to replace the former selenium one, and the relocation of the frame output transistor to the timebase PCB (previously it was mounted on a separate heatsink). These later models can easily be recognised by a BEAB sticker on the rear cover.

These sets are well known for poor tube life and being an 11” model a replacement tube isn’t the easiest of things to find. Fortunately this set (a post-1973 version) gave a nice bright raster when tried but a heavy 100Hz hum on the sound suggested that all was not well in the power supply so in the interests of not damaging the cathode the set was switched off quickly. Given that everything seemed functional and there was adequate width the fault had to be a simple one, either the reservoir capacitor open circuit of the filter transistor short. The latter proved to be the case; the transistor is located underneath and is housed in a TO3 package. Replacement isn't that easy since the “pin” side of the transistor isn’t accessible (even with the chassis removed) but the mounting screw are self tapping (no nuts on the other side) and there is just enough wire to pull through to be able to re-make the base and emitter connections if you are careful. I couldn’t find a 2SB407 (Sanyo) but a Newmarket OC28 came to had so that went in instead (see picture, note the 1974 date code!). This resulted in a small but hum-free picture and good sound with the main supply rail at about 10V, adjusting the filter bias control brought this up to 11.5V and the picture then filled the screen. The manual actually specifies 12V but 11.5 is more typical for mono portables, with the benefit that the width was spot-on correct. Note that this circuit is not a regulator, there is no error amplifier or voltage reference and so the supply line will change with mains voltage and load. The filter is not in-circuit for the 12V DC input to retain compatibility with the Sony Ni-CD battery pack so for car battery operation on of Sony’s external voltage regulators is required (as one uses with the TV9-90UB).

The results are now excellent, with a very sharp and nicely contrasted picture. The improved AGC makes for a real improvement over the TV9-90UB, although the vision stages are still AC coupled so the picture black level is not fully stabilised. These sets don’t seem to inspire the same affection as the earlier models (possibly due to the slightly blander styling and the tube problems) but a good one like this is a joy to watch, it’s a great addition to the collection.

bobbyball · 18th Mar 2013, 1:18 pm

Glad you found one at last Tim, you were lucky with the tube.

Robert

Heatercathodeshort · 18th Mar 2013, 8:35 pm

Great news Tim! I had thoughts of that power supply dishing out around 18v destroying the tube emission.
It was a pleasure to have you visit Tim and I really enjoyed plugging in all the telly junk some of which have not seen mains for a while. As I have said before, any Forum member will be made welcome here in West Sussex, providing that is you are interested in vintage telly junk.
Thanks for the gift by the way. Absolutely fantastic and it will add to my growing Sony collection. Regards, John.

18th Mar 2013, 8:55 am	#1
Studio263 Octode Join Date: Apr 2007 Location: Hampshire, UK. Posts: 1,577	Sony TV-110UK Forum member Heater-Cathode Short gave me this set at the weekend, I’ve been after a decent one for some time now but something that was once seemingly commonplace seems to have vanished from view of late, or maybe it’s just me… The Sony TV-110UK was introduced in 1971, at around the same time as the smaller TV-720UK, to broaden Sony’s UK range of monochrome portables. Neither of these sets replaced the well-known TV9-90UB, which continued to be available for those who required dual standard operation or the reliability of VHF reception. The TV-110UK was a larger set than had been offered in the range before, being an 11” model with a 90 degree tube. Compared to the TV9-90UB, the TV-110UK had more of a “big set” specification with proper line-gated AGC (at last!), increased boost HT supply for the video output stage, a generous 6 transistor audio section and electronic filtering for the AC power supply. The latter replaced the traditional choke filter which the previous models had used in conjunction with two large (4000uF) electrolytic capacitors with a much smaller capacitor and a simple one transistor circuit. Early issues of the circuit diagram show this drawn as part of the audio amplifier which can cause confusion; in fact the circuit is connected to the negative side of the selenium bridge rectifier. Some things didn’t change though; the frame timebase for example was almost unaltered from that used in the TV9-306UB of 1965. The design was updated in 1973 (along with the TV9-90UB) to meet BEAB requirements. The changes included revised power switching arrangements and a sprinkling of extra fuses, in the end no less than six were fitted, four of which were 200mA types feeding individual circuit stages. Other changes made at the same time included a new audio panel with a simplified 4 transistor circuit, a simplification which made room for a silicon bridge rectifier to replace the former selenium one, and the relocation of the frame output transistor to the timebase PCB (previously it was mounted on a separate heatsink). These later models can easily be recognised by a BEAB sticker on the rear cover. These sets are well known for poor tube life and being an 11” model a replacement tube isn’t the easiest of things to find. Fortunately this set (a post-1973 version) gave a nice bright raster when tried but a heavy 100Hz hum on the sound suggested that all was not well in the power supply so in the interests of not damaging the cathode the set was switched off quickly. Given that everything seemed functional and there was adequate width the fault had to be a simple one, either the reservoir capacitor open circuit of the filter transistor short. The latter proved to be the case; the transistor is located underneath and is housed in a TO3 package. Replacement isn't that easy since the “pin” side of the transistor isn’t accessible (even with the chassis removed) but the mounting screw are self tapping (no nuts on the other side) and there is just enough wire to pull through to be able to re-make the base and emitter connections if you are careful. I couldn’t find a 2SB407 (Sanyo) but a Newmarket OC28 came to had so that went in instead (see picture, note the 1974 date code!). This resulted in a small but hum-free picture and good sound with the main supply rail at about 10V, adjusting the filter bias control brought this up to 11.5V and the picture then filled the screen. The manual actually specifies 12V but 11.5 is more typical for mono portables, with the benefit that the width was spot-on correct. Note that this circuit is not a regulator, there is no error amplifier or voltage reference and so the supply line will change with mains voltage and load. The filter is not in-circuit for the 12V DC input to retain compatibility with the Sony Ni-CD battery pack so for car battery operation on of Sony’s external voltage regulators is required (as one uses with the TV9-90UB). The results are now excellent, with a very sharp and nicely contrasted picture. The improved AGC makes for a real improvement over the TV9-90UB, although the vision stages are still AC coupled so the picture black level is not fully stabilised. These sets don’t seem to inspire the same affection as the earlier models (possibly due to the slightly blander styling and the tube problems) but a good one like this is a joy to watch, it’s a great addition to the collection. Attached Thumbnails

18th Mar 2013, 1:18 pm	#2
bobbyball Octode Join Date: Jul 2011 Location: Stockport, Greater Manchester Posts: 1,214	Re: Sony TV-110UK Glad you found one at last Tim, you were lucky with the tube. Robert

18th Mar 2013, 8:35 pm	#3
Heatercathodeshort Dekatron Join Date: Jun 2005 Location: Warnham, West Sussex. 10 miles south of DORKING. Posts: 9,147	Re: Sony TV-110UK Great news Tim! I had thoughts of that power supply dishing out around 18v destroying the tube emission. It was a pleasure to have you visit Tim and I really enjoyed plugging in all the telly junk some of which have not seen mains for a while. As I have said before, any Forum member will be made welcome here in West Sussex, providing that is you are interested in vintage telly junk. Thanks for the gift by the way. Absolutely fantastic and it will add to my growing Sony collection. Regards, John.