Television RF Pre-amplifiers Models: A, B, C & D

Arthur Radford, before founding Radford Electronics, manufactured Television RF Pre-amplifiers through his company Cabot Radio Co. Ltd. in Bristol. These pre-amplifiers were designed to improve television signal reception and were available for both London and Birmingham frequencies.

Pre-amplifier Models
Cabot Radio offered several models of television pre-amplifiers:

• Model A: A two-stage model using 6SH7 valves with variable gain control, priced at £5.15.0 including valves.
• Model B: This model used a Mazda 6F1 valve and had an effective gain of 10 times with an extremely high signal-to-noise ratio. It could operate with an input as low as 5 microvolts without deteriorating picture quality. The bandwidth was 5 MHz, and it was entirely self-contained, operating from 200-250v A.C. 50 c.p.s. Priced at £5.15.0 including the 6F1 valve.
• Model C: A single-stage model using a 6SH7 valve, known for its high signal-to-noise ratio. It was priced at £4.17.6 including the valve.
• Model D: Another single-stage model using a 6SH7 valve, but it employed a capacitor for series heating the valve instead of a transformer. This model was the most affordable at £3.17.6 including the valve.

All models were self-contained with built-in power packs and operated from 200-250v 50 c.p.s. mains.

Technical Specifications
The Model B, in particular, stood out for its technical capabilities:

• Effective gain: 10 times
• Minimum input: 5 microvolts
• Bandwidth: 5 MHz
• Size: Approximately 4 inches cubed
• Valve: Mazda 6F1 in an up-to-date circuit1

These pre-amplifiers were available from local dealers or directly from Cabot Radio Co. Ltd. at 28 Bedminster Parade, Bristol.

Vous pourrez trouver sous ce lien 32 modèles d'appareils, 25 avec des images et 10 avec des schémas.
Tous les appareils de Radford Electronics Ltd.; Bristol