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Old 30th Mar 2020, 12:33 pm   #1
FERNSEH
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Join Date: Mar 2005
Location: Gateshead, Tyne and Wear, UK.
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Default The Ever-Ready experimental transistor TV set.

Now that I've been forced to close the shop during the Corona virus crisis I can get on with many outstanding restoration projects. The Ever-Ready all transistor TV set is one. Got to admit I was a bit reluctant to examine this set having been led to believe that there is some special circuits in the set. Well, it turns out most of the circuits are typical of early sixties transistor TVs such as the Pye TT1 and Ferguson 743T. In fact the IF PCB board in the E-R TV is from the Ferguson 743T. The reason for that is simple, Thorn laboratories did the design and construction of the set for the Ever-Ready company. ER made the special battery for the set, the TV1.
The circuits of the timebases have been traced out, the line oscillator control circuit apart there is nothing particularly special to comment about.
But the power supply arrangements is different and will be examined this week starting with the EHT generator. The attachment shows the internals of the EHT generator unit.
At least we have a brief description of the power supply arrangements. From page 122 of the December 1964 Practical Television magazine.
The Ever-Ready prototype Mk5 405 line transistor TV receiver. Extract from the description of the set.
"A separate blocking free-running oscillator feeding a five stage Cockroft-Walton multiplier provides EHT. A metrosil is employed to regulate EHT and give focus potential.
The particular triumph of the circuit is the stabilised power generator which maintains the battery volt-ampere product substantially constant. This employs three transistors, five diodes and a high ratio transformer with complicated suppression and smoothing."

On a small PCB we find a Mullard OC35 power transistor, an Ediswan XA701 and a Mullard PNP silicon OC703 transistor in the regulator circuit. Also two stud type diodes, a 6.2volt OAZ703 Zener diode and two small diodes, the types of those will be determined after further examination of the board.

DFWB.
Attached Thumbnails
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Last edited by FERNSEH; 30th Mar 2020 at 12:46 pm.
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