01-08-2015, 07:18 PM
(This post was last modified: 01-08-2015, 07:19 PM by Geordie McBoyne.)
Hi Trevor,
looking good, it is a pity we have to use modern resistors in old equipment. Are those old Soviet era resistors still available? Those resistors have a old fashioned look about them, and they are good.
Pictures of the TS701, the 7" vision and sound receiver. This one was made in 1939. The circuit design is very similar to the TSC30, the main difference apart from the type of CRT is the valves employed in certain parts of the circuit. The HT rectifiers are the Mazda UU5, (UU7 in the later set).
The line output valve is a Mazda AC6/PEN (PEN46). Frame output is a PEN45, (PEN46) The EHT rectifier is a Mazda U21, (U22).
The RF pentodes are Mazda SP41 in both sets.
In 1938 Ekco released the vision only receiver, the TA201, this set is also similar to the two sets discussed so far.
From the Valvepage website: http://www.thevalvepage.com/tvmanu/ekco/ekco.htm
I have never seen any service documentation for the 1937 models although looking at the picture of the TC103 I'd imagine the chassis construction is similar to the TSC902 (TSC30) The set will not use the SP41, it's likely the RF pentodes were the Mazda AC/SP3.
It also begs the question, what type of CRT? Electrostatic or Magnetic deflection? Bear in mind Ekco like Murphy and Ultra was signed up to Ediswan Mazda and in 1937 that firm did not make a magnetic CRT.
Today I found the drawings for the reconstruction of the TSC30 cabinet.
Geordie McBoyne.
looking good, it is a pity we have to use modern resistors in old equipment. Are those old Soviet era resistors still available? Those resistors have a old fashioned look about them, and they are good.
Pictures of the TS701, the 7" vision and sound receiver. This one was made in 1939. The circuit design is very similar to the TSC30, the main difference apart from the type of CRT is the valves employed in certain parts of the circuit. The HT rectifiers are the Mazda UU5, (UU7 in the later set).
The line output valve is a Mazda AC6/PEN (PEN46). Frame output is a PEN45, (PEN46) The EHT rectifier is a Mazda U21, (U22).
The RF pentodes are Mazda SP41 in both sets.
In 1938 Ekco released the vision only receiver, the TA201, this set is also similar to the two sets discussed so far.
From the Valvepage website: http://www.thevalvepage.com/tvmanu/ekco/ekco.htm
I have never seen any service documentation for the 1937 models although looking at the picture of the TC103 I'd imagine the chassis construction is similar to the TSC902 (TSC30) The set will not use the SP41, it's likely the RF pentodes were the Mazda AC/SP3.
It also begs the question, what type of CRT? Electrostatic or Magnetic deflection? Bear in mind Ekco like Murphy and Ultra was signed up to Ediswan Mazda and in 1937 that firm did not make a magnetic CRT.
Today I found the drawings for the reconstruction of the TSC30 cabinet.
Geordie McBoyne.
