Description: The filament tests good. My emission tester doesn't have a roll chart entry for this tube, so I checked emission as follows: 1. Set filament voltage 6.3 VAC. 2. Put 21.3 VAC (rms) between plate and cathode.3. Grid connected to plate. 4. Measured 10.5 mA (DC average) plate current under the conditions above. With the tube behaving as a half wave rectifier and 21.3 VAC (rms) between plate and cathode, this corresponds to 30 V (peak), and 30/pi = 9.6 V (average). So we have 10.5 mA flowing with 9.6 VDC between plate and cathode. The datasheet isn't so clear at these low voltages but this seems reasonable. Since this is a power tube meant to be used at much higher plate voltages, I think that the tube is good. The cap on the top of the tube fell off but I'll include the cap. There is enough wire to reattach it. This is the EXACT TUBE in the tube tester shown. Only the vacuum tube is being sold. No box. Shipping only to lower 48 states.Seller Label #42
Price: 25 USD
Location: Grant City, Missouri
End Time: 2025-01-29T17:38:41.000Z
Shipping Cost: 6 USD
Product Images
Item Specifics
All returns accepted: ReturnsNotAccepted
Brand: RCA
Type: Vacuum Tube
MPN: 811A
Unit Quantity: 1
