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I'll take it. Russ [email protected]> wrote:

Hello?? Free for USPS Postage, probably Medium Flat rate box, to the lower 48.Insured. Let us know how much insurance you need for this meter. We use lots of bubble wrap !! This meter is not

Update: The output of the TR switch to the receiver is a bit more manageable driving it with 30 watts (see photo) than with the 10 watts I ran in my previous post: Assuming the maximum safe input to

I am looking for a Johnson Signal Sentry, Part No. 250-25. Thanks! Mike Harmon, WB0LDJ mharmon at att dot net

Work to be done ... ? About 10 watts into the TX jack and then on to a 50Ω dummy load from the Antenna jack ? Yields about 9.8 Vpp / 3.5 Vrms? across 50Ω into my scope (thankfully not my

*For Sale: Johnson Viking Valiant 1* This radio is in good overall shape and appears to be complete. It is untested. Condition is commensurate with age with some “patina”, especially on the rear

Hi Sully , No, I have (3) of the Johnson TR switches. I’m talking about a device called the Signal Sentry. It’s basically a keying monitor, but it has other benefits as well. I’d like to find

Anyone contemplating using the EF Johnson T/R switch with anything other than a tube-type receiver should read Tom Rauch W8JI's comments: https://www.w8ji.com/johnson_tr_switch.htm Not wanting to

Could you be talking about the Johnson T/R switch? I have one of those and am in the process of setting up an AM station with a Viking I transmitter and this switch. Right now I am trying to decide

Mike, Have you ever heard of a Johnson Signal Sentry? I just found out about them today, and the operation sounds intriguing. Apparently, the gadget mutes the receiver during transmit and sends an

OK – noting that you’re thinking of using the HV FET to open the B+, I would ask two questions, please. If you’re inclined to do it this way, might you consider just killing the audio output

For break-in, I’m thinking that opening and closing circuits with the lowest voltage and least current along with not having capacitors that need to discharge to fully mute the receiver would be

Hi Mike, I’ve been thinking of alternative ways of doing what I wanted to accomplish. As constructed, the Collins R-388 receiver has a terminal strip on the rear apron that is connected to a DC

Hmmm. Interesting idea ! Please allow me to share two thoughts. If you sense voltage across the key rather than at the “Probe” port, you’ll preclude any even small delay in reducing receiver

Hi, Mike, I share your thoughts. I was thinking of rectifying the voltage from the "Probe" port on the TR Switch to turn on a transistor, which would apply a control voltage across a small relay.

Thanks for the reply, Mike. Both sections of C12 were horrible. I had restuffed the can with new caps which explains the OPEN and supports your theory. Jeff W8KZW

Hello Jeff! From the diagram on the back page of my T-R switch instructions (Figure 2) it appears that Johnson is estimating the DC leakage in C12A and C12B, the power supply filter capacitors. That

It is one of those "I should know this but ..." questions. For the Johnson 250-39 TR switch, Table I presents the resistance at pins 2 and 5 of the 6BL7 as 100K ohms. For the life of me, looking at

Watch You Tube vidios on the Viking II.? Only slight difference is the final loading. Lee, w0vt

I have a Viking I transmitter. Anyone know of any videos that sow how to bring it on line a transmit. It is not as straight forward as today's amateur gear and I am having trouble finding anyone who