First Television to use ICs - Page 3 - UK Vintage Radio Repair and Restoration Discussion Forum

toshiba tony · 9th Aug 2019, 5:20 pm

Was the SL901 exclusive to the single chip A823, don't recall seeing it elsewhere.

Ferguson 2000 · 10th Aug 2019, 12:40 am

The first IC that I changed was in a EKCO / Pye B/W set for a local dealer and before solder suckers and solder wick! I think that it was for sound demodulation.

The early RBM A823 used a SL901 with 20 pins and a heatsink, later sets used the SL901B which had 24 pins and no heatsink. All the sets that I saw with the SL901B also used the SL917A for chroma etc.

RBM produced a meter to set up the level of burst / chroma with 3 leads, I still have one somewhere but it has been a long time since I last used it.

dazzlevision · 10th Aug 2019, 5:12 am

Quote:

Originally Posted by toshiba tony

Was the SL901 exclusive to the single chip A823, don't recall seeing it elsewhere.

This was also used in the RBM 22” dual standard colour TV chassis: Murphy CV2210D and Bush CTV174D.

Welsh Anorak · 15th Aug 2019, 2:20 pm

Yes - the CTV174D proudly proclaimed "IC Colour Lock" on the front panel!
The SL901 originally used was mounted on the 'wrong' side of the decoder panel and had the heatsink horns coming out of it. Pre solder wick, most panels were badly damaged when someone had used a 50W Weller to remove it.
The power supply, IF and timebases were pure CTV25/162 Mk3, but the decoder and output (now RGB and transistorised) panels were completely redesigned. I wondered if the use of the SL901 was to road test the IC before using it in the A823?

toshiba tony · 15th Aug 2019, 2:48 pm

Re Glyn's comment on the SL901, was it now! I thought it was made for the 823. I was in the trade even then but I dont recall it's use in the earlier chassis.
But I remember the Australian PCL82 in the Bush TV125 (upside down)
Strange how some things stick in the mind and some don't. And that caused issues being inverted. Cathode coating falling off perhaps? Sets seemed happy having their valves horizontal though.

greg_simons · 15th Aug 2019, 5:29 pm

Quote:

Originally Posted by Welsh Anorak

Yes - the CTV174D proudly proclaimed "IC Colour Lock" on the front panel!
The SL901 originally used was mounted on the 'wrong' side of the decoder panel and had the heatsink horns coming out of it. Pre solder wick, most panels were badly damaged when someone had used a 50W Weller to remove it.
The power supply, IF and timebases were pure CTV25/162 Mk3, but the decoder and output (now RGB and transistorised) panels were completely redesigned. I wondered if the use of the SL901 was to road test the IC before using it in the A823?

Yes indeed, saw quite a few mega botch repairs on these panels although the 901/917 were rarely to blame, most people went straight for the chips first instead of logical diagnosis, i suspect many blameless chips went in the bin after being brutally removed from the panel, can't say i ever was a big fan of the 823, even well set up they seemed to have a slight green overall hue and the general performance wasn't great.
Greg.

9th Aug 2019, 5:20 pm	#41
toshiba tony Heptode Join Date: May 2006 Location: Accrington, Lancashire, UK. Posts: 978	Re: First Television to use ICs Was the SL901 exclusive to the single chip A823, don't recall seeing it elsewhere.

10th Aug 2019, 12:40 am	#42
Ferguson 2000 Tetrode Join Date: Jun 2008 Location: Stratford upon Avon, Warwickshire, UK. Posts: 80	Re: First Television to use ICs The first IC that I changed was in a EKCO / Pye B/W set for a local dealer and before solder suckers and solder wick! I think that it was for sound demodulation. The early RBM A823 used a SL901 with 20 pins and a heatsink, later sets used the SL901B which had 24 pins and no heatsink. All the sets that I saw with the SL901B also used the SL917A for chroma etc. RBM produced a meter to set up the level of burst / chroma with 3 leads, I still have one somewhere but it has been a long time since I last used it. __________________ Best wishes, Geoffrey.

15th Aug 2019, 2:20 pm	#44
Welsh Anorak Dekatron Join Date: Apr 2005 Location: North Wales, UK. Posts: 6,918	Re: First Television to use ICs Yes - the CTV174D proudly proclaimed "IC Colour Lock" on the front panel! The SL901 originally used was mounted on the 'wrong' side of the decoder panel and had the heatsink horns coming out of it. Pre solder wick, most panels were badly damaged when someone had used a 50W Weller to remove it. The power supply, IF and timebases were pure CTV25/162 Mk3, but the decoder and output (now RGB and transistorised) panels were completely redesigned. I wondered if the use of the SL901 was to road test the IC before using it in the A823? __________________ Glyn www.gdelectronics.wales

15th Aug 2019, 2:48 pm	#45
toshiba tony Heptode Join Date: May 2006 Location: Accrington, Lancashire, UK. Posts: 978	Re: First Television to use ICs Re Glyn's comment on the SL901, was it now! I thought it was made for the 823. I was in the trade even then but I dont recall it's use in the earlier chassis. But I remember the Australian PCL82 in the Bush TV125 (upside down) Strange how some things stick in the mind and some don't. And that caused issues being inverted. Cathode coating falling off perhaps? Sets seemed happy having their valves horizontal though.