cablehack
DSCF1687
The 5BP1 CRT was announced by RCA in November of 1938, under the pre RMA number, 1802-P1. It was designed for television and oscillographs. A white phosphor tube 5BP4/1802-P4 was intended for television only, although it did appear in at least one war time oscilloscope - its white phosphor being more grainy. The 1802-P4 was used in the RCA TRK-5 and TT-5 televisions of 1939. Meissner also had a kit with the same tube. Andrea appears to have given the option for either the P1 or P4 tube in their set.
The 1802 was popular for wartime radar and oscilloscope type instruments, and as a result was very plentiful and cheap in disposals stores post war.
With a good tube correctly focused and shielded, the 5BP1 image looks as though it's etched on the glass, it's that sharp.
See article here members.iinet.net.au/~cool386/5BP1/5%20inch%20TV%20receiv...
DSCF1687
The 5BP1 CRT was announced by RCA in November of 1938, under the pre RMA number, 1802-P1. It was designed for television and oscillographs. A white phosphor tube 5BP4/1802-P4 was intended for television only, although it did appear in at least one war time oscilloscope - its white phosphor being more grainy. The 1802-P4 was used in the RCA TRK-5 and TT-5 televisions of 1939. Meissner also had a kit with the same tube. Andrea appears to have given the option for either the P1 or P4 tube in their set.
The 1802 was popular for wartime radar and oscilloscope type instruments, and as a result was very plentiful and cheap in disposals stores post war.
With a good tube correctly focused and shielded, the 5BP1 image looks as though it's etched on the glass, it's that sharp.
See article here members.iinet.net.au/~cool386/5BP1/5%20inch%20TV%20receiv...