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1963 Ever-Ready experimental all-transistor TV set.  

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Katie Bush
(@katie-bush)
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Posted by: @till

Hi Doz,  the battery compartment is 130 x 133 x 63mm so anything smaller than this can be fitted.

 

Ah right, so that also let's the NP7-12 out of the race! But, there are smaller batteries in the range.

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Posted : 04/06/2020 8:12 pm
Katie Bush
(@katie-bush)
Famed V-Ratter Moderator

There is an NP4-12 that comes at 106 x 90 x 70, so we're getting closer!   I wonder if there's an NP2-12. . . .

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Posted : 04/06/2020 8:18 pm
Katie Bush
(@katie-bush)
Famed V-Ratter Moderator

NP2-12 s now discontinued, but there is an NP3-12 which comes in at 134 x 67 x 64. So that's a 12v battery at 3Ah.

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Posted : 04/06/2020 8:23 pm
Katie Bush
(@katie-bush)
Famed V-Ratter Moderator

Or, an NP1.2-12 at 97 x 48 x 50 - That'll fit in there! 1.2Ah

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Posted : 04/06/2020 8:26 pm
Till Eulenspiegel
(@till)
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Hi Marion, excellent research, many thanks for that. 

https://www.benchmarkminerals.com/membership/nickel-the-often-forgotten-battery-metal/

Just after four hours use the AA cells finally failed, reached a point in time when the terminal voltage of the battery suddenly went down to 3volts. Cells were very warm. How long would the set operate on eight D cells?  Something try next.

Till Eulenspiegel.

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Posted : 06/06/2020 9:06 pm
Katie Bush
(@katie-bush)
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Posted by: @till

Just after four hours use the AA cells finally failed, reached a point in time when the terminal voltage of the battery suddenly went down to 3volts. Cells were very warm. How long would the set operate on eight D cells?  Something try next.

Till Eulenspiegel.

I would not be surprised to find that they don't last a great deal longer. Given the manufacturers' ability to selectively tailor the "energy density" of their products, there would seem to be little difference between AA and AAA, and then again C and D cells, in terms of run time. I remember watching a YouTube video of a guy dismantling various cells, and was aghast at the miniscule amount of contents within a particular D cell, to point of fact, it was an AA cell inside a D cell jacket!

I'd guess that 10 x 'High Density' AA NimH (say, 2500 mAh) would be another possible route? - Probably a bit pricey, but doable.

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Posted : 06/06/2020 9:38 pm
Cathovisor
(@cathovisor)
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@till

The piece on nickel reminded me of an ongoing project at the Nene Valley Railway to restore a matching trailer car for a Swedish railcar there; that was fitted with nickel-iron cells. How did NiFe fall out of the battery equation?

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Posted : 07/06/2020 2:24 pm
turretslug
(@turretslug)
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ISTR (and it's all a bit sketchy, so I stand to be corrected) that NiFe cells were amongst the first secondary types to be used but had a relatively low capacity-to-bulk/weight ratio compared to later types, also the relatively low (again ISTR) 1.1V/cell was awkward in batteries compared to nearly double that from PbSO4- more separater/container space, more inter-linking. They were supposed to be very dependable and robust (e.g. without the plate/layer susceptibility of lead-acid to vibration and shocks), though, and uncritical on charge/discharge regimes and didn't mind abuse like being left flat for long periods. Hence, they got used for railways, early telephone exchanges and other applications like marine usage and even early submarines where weight wasn't so critical but you needed something that wouldn't let you down.

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Posted : 07/06/2020 5:23 pm
Till Eulenspiegel
(@till)
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Meanwhile during the discussions about finding a suitable battery for the E-R TV set the sync separator transistor failed, dead short between collector and emitter.  The sync separator transistor is located on the Ferguson sourced IF, audio and video board. The transistor is an OC45, well known for it's use in 1950s and early '60s radios as an IF amplifier. I've got limited stock of this type and would prefer to use the transistor in radio sets so a substitute must be found. An OC200 was tried first but the B-E junction potential of 0.7V rendered the transistor unsuitable as the sync separator in this set. Instead, a Hitachi 2SA15 has been tried out. The 2SA15 was a transistor used as the frequency changer in radio sets. It's a near equivalent to the OC44.

https://www.radiomuseum.org/tubes/tube_2sa15.html

Anyway, the substitute transistor is working well as the sync separator, see the attachments. The RS PRO oscilloscope doesn't have a delay function so the frame pulses are shown at the start of the trace.

Interesting to note a transistor was used as the sync separator in the 1961 range of 405 line Pye TV sets. I don't think there was any technical merit for using a transistor for the sync separator function, more likely a sales gimmick, "transistor synchronised" Sounds good doesn't it? 

But Pye did make and market a transistor TV set in 1961, the model TT1. And it has a big 14" CRT.

Till Eulenspiegel.

ER TV sync F
ER TV sync L
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Posted : 07/06/2020 7:07 pm
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Doz
 Doz
(@doz)
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Till, you have a PM

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Posted : 08/06/2020 12:00 pm
Katie Bush
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@turretslug

Back in the 1950s, David Brown Tractors offered "NiFe" batteries on any of their electric start models. These batteries were said to be the best that money could buy, and could outlast anything else currently available. It was suggested that the batteries would last the probably working life of the tractor.

Interestingly, our physics laboratory at my secondary school also used NiFe batteries, which if I recall were manufactured by Alcad, and apparently because they could withstand a lot of abuse without detriment to their performance. It also seems that the UK military used/uses NiFe batteries on their larger, static standby generators - on airfields etc. as did/do many other applications such as hospitals and Government installations where reliable battery back-up and engine starting capability is a must. Seemingly, by Alcad.

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Posted : 08/06/2020 2:07 pm
Nuvistor
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My father in law worked at David Browns in Leigh Lancs in the 1950’s. He was a welder.

 

Frank

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Posted : 08/06/2020 10:30 pm
turretslug
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I'm trying to remember the context, but I recall some NiFe cells in our physics lab, too, quite tall and slim metal-jacketed things in hardwood boxes. I wouldn't be surprised if they were ex-military. BTW, weren't old-style physics labs wonderful places? (in my case late '70s/early '80s). Ours included chain-hoists for illustrating mechanical advantage, a 0-6kV variac-driven power pack with 4mm terminal posts (!), a vast induction coil producing sparks several inches long (that we were kept well away from) for lighting up Geissler tubes, Griffin and George skeleton transformers whose secondaries would melt large nails and a couple of AVO valve testers. I expect that they're very safe and sanitary places nowadays.

On the subject of big and dependable batteries, I recall reading in the paper as a kid about the mysterious discovery of large NiCd drum batteries in Northern Canada and how people were scratching their heads over it;

https://en.wikipedia.org/wiki/Weather_Station_Kurt

 

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Posted : 08/06/2020 10:50 pm
Till Eulenspiegel
(@till)
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A fault still exists in the line blanking pulse which can be corrected by fitting a 10Kohm resistor between the base and emitter of the line blanking transistor.

ER TV Line blkg 1
ER TV Line blkg 2
ER TV Line Frame Blkg cct

 

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Posted : 09/06/2020 11:41 am
Nuvistor liked
Till Eulenspiegel
(@till)
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When the contrast control is at a high setting the sync pulses are perfect. However, at lower settings and on certain picture scenes the sync pulses are crushed. It has been determined that the likely cause of the problem exists in the final IF amplifier stage. There is a possibility of rectification of the IF signal taking place in the transistor. A 60mV P - P video signal is present across the emitter resistor of the final IF transistor.   

Ever Ready TV Final IF

Till Eulenspiegel.

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Posted : 01/08/2020 6:57 pm
Nuvistor liked
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