For sale are VR91 (EF50) classic red VHF pentode amplifier valves / vacuum tubes by Sylvania on B9G base. All fully tested and working no faults. These are original Air Ministry valves supplied to the UK from the USA at some point before World War II, also labelled 10E/92, the pre-CV ministry number (CV1091).

The EF50 was the famous valve of WWII and is often described as the "valve that won the war". Originally designed for very early television IF work, it was extensively adopted for use in early radar and communications systems.

These particular examples have all original markings are present on the traditional red aluminium can, fully readable. All are tested at 100% of nominal new emission.

This particular example tests great on my Mullard High Speed Valve tester showing zero faults and 90% of nominal new emission. A sensible price for fully working, usable example of an interesting and now historic old device.

EF50 / CV1091 / VR91 / 63SPT

Heater = 6.3V @ 0.3A

Pentode:
Anode / Plate:  250V / 10mA / 1.0Mohm
Screen Grid: 250V / 3mA
Signal Grid: -2.0V
gm: 6.5mA/V

I offer a full, money back guarantee if you are not completely satisfied with this purchase (see terms). We have been trading since 1927 so bid with confidence. Most of our valves / tubes have been in our own stock room for many, many years. See our EXCELLENT FEEDBACK on quality valves / tubes previously supplied!

We have thousands of valves / tubes in stock - standard and rare; US, UK and European. If you have any particular requirements, please send a message and if we have what you want, we will list it here.

We ship worldwide and are very happy to combine items for multiple postage.

TERMS

GUARANTEE: In case of dissatisfaction, buyer must return item at own expense. We will only refund if you return the EXACT SAME VALVE / TUBE to us that you have purchased, with the heater still intact and passing continuity test. Believe it or not, some evil people have tried to send us back their dud tubes to try and get a full refund for a perfectly good tube we have just sold them! So, refund is a genuine offer, but at our discretion that we have been sent back what we actually sold you in the first place and you have not destroyed it through misuse!

PAYMENT: We accept Paypal, cheques in GBP, UK postal orders / bank drafts or bank transfer. Please CONTACT US FIRST before sending payment by a method other than PayPal - there will be a delay in shipping while we clear your payment if you pay using these other methods. We are happy for you to collect from Bristol, but will require payment in GBP cash on collection.