I've been looking around still for a 16bnp4 for my portable airline set to replace the weak tube it has, but it seems this is a pretty obscure tube. On another forum a member suggested the tube 16bdp4 may work. I looked over the two and the characteristics are pretty darn close. The only real major difference I noticed is that the neck length of the 16bdp4 is shorter than the 16bnp4 by a little bit. Can anyone with more knowledge on subbing crts look over the data sheets for the two and let me know if this would work or not? Thanks so much for the help and here are the links to the crt data sheets

16bnp4:
http://frank.pocnet.net/sheets/201/1/16BNP4.pdf

16bdp4:
http://frank.pocnet.net/sheets/201/1/16AYP4.pdf

Doesn't sound good to me. One is magnetic deflection, and the other is electrostatic deflection.

Where do you see that? It only says the Focusing is Electrostatic on both tubes.

The 16BNP4 doesn't specify what deflection is used but a 16" tube with a 103 deg angle isn't likely to be Electrostatic.

Sorry, I am indeed in error. Due to the info pages being in different formats, I didn't do a good job of looking at them when I brought them up side by side. I stopped as soon as I saw "electrostatic" on one and "magnetic" on the other.

Both tubes are 114 degree overall deflection.

Ok, I looked over both datasheets and the two seem pretty compatable, the only major difference I noticed that could cause a problem is that the 16bdp4 is supposed to have a g2 voltage between 550 and 200 volts while the 16bnp4 is only rated for between 60 and 25 volts. I don't know enough about crts to know what too low a g2 voltage would do to the set. Looking at the schematic for the airline set, the set taps off the 135v line and through some resistors drops the voltage to 50v.

Here's a good sub chart over at ETF. It doesn't show the two you are looking for specifically but is very helpful in other cases
http://www.earlytelevision.org/pdf/crt_cross_reference_manual.pdf

Hi, Looking over the specs' of the two CRTS the 16BDP4 has a 450 ma. heater and the 16BNP4 has a 600 ma. heater. Also the 16BNP4 only needs about 30 volts peak to peak drive signal. Where as the 16BDP4 needs 100 volts peak to peak drive signal. The G-2 voltage and heater current can be taken care of just by using resistors. The 100 volt peak to peak video drive signal not so easy. You should test the CRT maybe a lite cleaning on restore mode of a SENCORE tester is all it needs. I would try a pass on the CRT tester and keep looking for a tube that has specs close to the tube you half now, but make sure it is a low drive tube. All the best,tom.j.fla

Hi, Looking over the specs' of the two CRTS the 16BDP4 has a 450 ma. heater and the 16BNP4 has a 600 ma. heater. Also the 16BNP4 only needs about 30 volts peak to peak drive signal. Where as the 16BDP4 needs 100 volts peak to peak drive signal. The G-2 voltage and taking care of the heater current is easy jut using resistors. The 100 volt peak to peak video drive signal not so easy. You should test the CRT maybe a lite cleaning on restore mode of a SENCORE tester is all it needs. I would try a pass on the CRT tester and keep looking for a tube that has specs close to the tube you half now, but make sure it is a low drive tube. All the best,tom.j.fla

Here's a good sub chart over at ETF. It doesn't show the two you are looking for specifically but is very helpful in other cases
http://www.earlytelevision.org/pdf/crt_cross_reference_manual.pdf

http://videokarma.org/showpost.php?p=3139100&postcount=10

Newer, with a Color CRT sub chart as well. NOT inclusive, not "the last word," but potentially helpful to someone.