View Full Version : 7jp4 VS 7vp1


timmy
02-05-2018, 09:22 AM
Can a 7vp1 take the place of a 7jp4 crt , what is the difference between the 7v and 7j besides the green screen. :scratch2:

dieseljeep
02-05-2018, 09:42 AM
Can a 7vp1 take the place of a 7jp4 crt , what is the difference between the 7v and 7j besides the green screen. :scratch2:

Not much! Works fine as a test tube. :thmbsp:

EdKozk2
02-05-2018, 11:26 AM
Hi Timmy,
You have watch that you don't exceed the maximum anode voltage for the 7VP1. It is designed for voltages only up to 4000, not 6000 like the 7JP4. The 7VP series crts were for scopes mainly.
Ed

bandersen
02-05-2018, 11:36 AM
Exactly. Here's the full datasheet: https://frank.pocnet.net/sheets/049/7/7VP1.pdf


Taken from this excellent website that has data on just about every tube and CRT ever made.

https://frank.pocnet.net/

jr_tech
02-05-2018, 02:03 PM
Does anybody here have a 7 inch set that will actually make 6 kV? :scratch2:

jr

compucat
02-05-2018, 04:16 PM
Does anybody here have a 7 inch set that will actually make 6 kV? :scratch2:

jr

My Motorola 9VT1 will make 6kV. It uses the TS-18 chassis. Although it is the 8 inch model, it uses the same chassis as the 7 incher.

Penthode
02-08-2018, 12:21 AM
A 7VP1 is good if you want green laggy pictures!

bandersen
02-08-2018, 09:06 AM
I use them all the time. There is also a 7JP1 and 7GP1. They are very useful while working on a chassis while the more valuable 7JP4 is stored safely away. I don't really notice a lag.

https://youtu.be/GR_3SSr96Us?t=21m12s

jr_tech
02-09-2018, 12:17 PM
A 7VP1 is good if you want green laggy pictures!

IMHO, green is fun for a change, I usually have a 3KP1 in my Pilot, as it seems to generate more interest, and promotes a little discussion of various phosphor types with visitors. The 3KP4 spends most of the time safely stored away in the closet. I don't notice lag when using the P-1 jug, in fact, measured decay times to the 10% level are similar to P-4 (20-30ms), with P-4 actually at the high end of the range.

https://farm5.staticflickr.com/4496/37509422092_2e118716a6_m_d.jpg

Green is Good,
jr

Tom9589
02-09-2018, 03:53 PM
The P7 phosphor is the one with the long decay time. I once bought a "test" tube from Olson Electronics (remember them?) with a P7 phosphor. It worked great and didn't need an ion trap.

compucat
02-09-2018, 04:02 PM
IMHO, green is fun for a change, I usually have a 3KP1 in my Pilot, as it seems to generate more interest, and promotes a little discussion of various phosphor types with visitors. The 3KP4 spends most of the time safely stored away in the closet. I don't notice lag when using the P-1 jug, in fact, measured decay times to the 10% level are similar to P-4 (20-30ms), with P-4 actually at the high end of the range.

https://farm5.staticflickr.com/4496/37509422092_2e118716a6_m_d.jpg

Green is Good,
jr

I wonder if you could put a magenta filter in front of that and have it show up grey.

jr_tech
02-09-2018, 05:21 PM
I wonder if you could put a magenta filter in front of that and have it show up grey.

Nope, P-1 has almost zero output at the red and blue ends of the spectrum.

jr