K.B. RV10 revival. - UK Vintage Radio Repair and Restoration Discussion Forum

Heatercathodeshort · 4th Dec 2005, 7:43 pm

Hello,
It was 5pm at Harpenden and this little KB RV10 needed a good home. despite my promise to come home with nothing I managed to fill the car with yet more dusty electronics...
The KB RV10 was the first of a series of excellent television receivers made by Standard Telephones that peaked with the VC53 series hand wired dual standard chassis. This model was released late in 1959 for the 1960 season and to some extent was out of date due to its 90 degree tube. Most manufacturers had gone over to 110 degree tubes by 1959 and KB were a little late with this model. This set uses the BRIMAR C17SM 17" 90 degree, electrostatic focus but no ion trap. It gives an excellent picture.
I repaired many of these sets in the 60's and they made great
sets for the second hand market.
The job entailed no more than would have been required when the set was say 6 years old needing a few of the wax capacitors replaced and a few resistors that had gone 'high'. The set uses the high gain 'Fireball' tuner of American design and this is reflected by the single vision I.F. stage and the high sensitivity of the set. Very little appears to have been replaced during its life. The H.T. rectifier has been replaced with the usual silicon diode kit and the tuner valves are date coded 1971. I feel the set was used near to the end of the 405 transmissions as the chassis is in such good condition.
These sets are considered to be a bit boring by collectors but make excellent start projects for those not too experienced with old television technique. They are not easily blown up and not many tears need be shed if you managed to do just that!
Pictures show the front view, signal provided by 405 tape recorded in 1980. Underchassis view, top view and the fireball tuner with its coil disk removed for cleaning. Go on......Have a go....
Regards. JOHN.

David_Robinson · 5th Dec 2005, 1:48 pm

I have a slightly later model, the QF80 with 110° tube and FM radio:

http://homepage.ntlworld.com/david.r...20Majestic.JPG

http://homepage.ntlworld.com/david.r...20Card%20F.JPG

It's amusing how they used just a small PCB, as if they didn't trust this new fangled technology but thought they would just give it a little go.

One question, is the interlace good on your set? The only way I managed to do it was with a mod to include an interlace pot à la Bush TV135.

Heatercathodeshort · 5th Dec 2005, 5:59 pm

Hello David,
INTERLACE.....Yes its very good on this set but was non existant on the 110 degree models [RV and related models] due to a design fault with the scanning coils. There is a degree of coupling between the line and frame coils increased by the use of a closed loop sleeve for width control [NASTY but used for years by many makers after 1958] If this is twisted it actually aids the coupling between the coils. This result is nill interlace but the public never noticed and if you had asked them to spend say £12 on coil replacement they would have thought it money wasted...K.B. introduced an improved yoke but it was rarely requested. Nothing has changed and as I have always said, if the picture stays still and the sound comes out of both speakers, they are happy. High definition television? Simple, first you degrade the picture [Plasma/LCD] then improve technology a bit then reintroduce crt quality and call it H.D....... I've been around too long..
Regards. JOHN.

4th Dec 2005, 7:43 pm	#1
Heatercathodeshort Dekatron Join Date: Jun 2005 Location: Warnham, West Sussex. 10 miles south of DORKING. Posts: 9,147	K.B. RV10 revival. Hello, It was 5pm at Harpenden and this little KB RV10 needed a good home. despite my promise to come home with nothing I managed to fill the car with yet more dusty electronics... The KB RV10 was the first of a series of excellent television receivers made by Standard Telephones that peaked with the VC53 series hand wired dual standard chassis. This model was released late in 1959 for the 1960 season and to some extent was out of date due to its 90 degree tube. Most manufacturers had gone over to 110 degree tubes by 1959 and KB were a little late with this model. This set uses the BRIMAR C17SM 17" 90 degree, electrostatic focus but no ion trap. It gives an excellent picture. I repaired many of these sets in the 60's and they made great sets for the second hand market. The job entailed no more than would have been required when the set was say 6 years old needing a few of the wax capacitors replaced and a few resistors that had gone 'high'. The set uses the high gain 'Fireball' tuner of American design and this is reflected by the single vision I.F. stage and the high sensitivity of the set. Very little appears to have been replaced during its life. The H.T. rectifier has been replaced with the usual silicon diode kit and the tuner valves are date coded 1971. I feel the set was used near to the end of the 405 transmissions as the chassis is in such good condition. These sets are considered to be a bit boring by collectors but make excellent start projects for those not too experienced with old television technique. They are not easily blown up and not many tears need be shed if you managed to do just that! Pictures show the front view, signal provided by 405 tape recorded in 1980. Underchassis view, top view and the fireball tuner with its coil disk removed for cleaning. Go on......Have a go.... Regards. JOHN. Attached Thumbnails

5th Dec 2005, 1:48 pm	#2
David_Robinson Retired Dormant Member Join Date: Feb 2004 Location: Nottingham, UK Posts: 94	Re: K.B. RV10 revival. I have a slightly later model, the QF80 with 110° tube and FM radio: http://homepage.ntlworld.com/david.r...20Majestic.JPG http://homepage.ntlworld.com/david.r...20Card%20F.JPG It's amusing how they used just a small PCB, as if they didn't trust this new fangled technology but thought they would just give it a little go. One question, is the interlace good on your set? The only way I managed to do it was with a mod to include an interlace pot à la Bush TV135.

5th Dec 2005, 5:59 pm	#3
Heatercathodeshort Dekatron Join Date: Jun 2005 Location: Warnham, West Sussex. 10 miles south of DORKING. Posts: 9,147	Re: K.B. RV10 revival. Hello David, INTERLACE.....Yes its very good on this set but was non existant on the 110 degree models [RV and related models] due to a design fault with the scanning coils. There is a degree of coupling between the line and frame coils increased by the use of a closed loop sleeve for width control [NASTY but used for years by many makers after 1958] If this is twisted it actually aids the coupling between the coils. This result is nill interlace but the public never noticed and if you had asked them to spend say £12 on coil replacement they would have thought it money wasted...K.B. introduced an improved yoke but it was rarely requested. Nothing has changed and as I have always said, if the picture stays still and the sound comes out of both speakers, they are happy. High definition television? Simple, first you degrade the picture [Plasma/LCD] then improve technology a bit then reintroduce crt quality and call it H.D....... I've been around too long.. Regards. JOHN.