The Electronics Universe

Test Equipment => Volt Meters => Topic started by: UNIT_399 on October 13, 2014, 07:22:16 PM

Title: HELPER RF-801 RF Millivoltmeter
Post by: UNIT_399 on October 13, 2014, 07:22:16 PM
The Colombian army closed one of its bases near us, and the base commandante (who is a good friend) asked if I wanted any of the equipment in the electrical maintenance facility before he had it shipped to Bogota. Most of the stuff I already had, but I did pick up a B&K 200 mhz freq counter, an SL-501 Sinad tester, and a Helper RF-801 RF millivoltmeter. Everything was in like new condition, but the millivoltmeter is missing the rf probe. The probe schematic is in the manual, but without any component values. The schematic is shown below.

Helper instruments sold out in 1999, and the purchaser has long ago discarded all of the files for the RF-801.

If anyone has a probe they would sell, or can help out with the component values so I can build one, please PM me or email me at unit399@yahoo.com. From reading the owner's manual, the meter won't function properly w/o the factory probe, and I hate to see a nice piece of equipment like this go unused.
Title: Re: HELPER RF-801 RF Millivoltmeter
Post by: The Radio Shop on October 19, 2014, 07:44:17 PM
I will keep am eye out bro. But may be as easy as building one yourself. I have built a lot of my probes.
BTW, welcome to the forums
Title: Re: HELPER RF-801 RF Millivoltmeter
Post by: UNIT_399 on October 21, 2014, 11:02:39 PM
RT -

Thanks for the welcome. I would build one myself IF I had the values for the components in the probe schematic. I have a Boonton rf voltmeter that uses a similar probe, but the Helper won't calibrate with it. From what I've learned from calling around, the Helper probe is the only one that will work.
73s.

- 399
Title: Re: HELPER RF-801 RF Millivoltmeter
Post by: The Radio Shop on October 28, 2014, 05:19:10 PM
Ok, as soon as I am fininish with the shop remodel I will se if I can come up for a solution for you.
I am sure we can get the correct values together to make one work.