S-Meter - Tuning Indicator


James Lawrie
 

Hello,

Kinda of topic maybe, but I scored a few combo S-Meter and Tuning Indicator meters that appear to be for a high end Stereo and am looking for an S-meter and Tuning indicator circuit that can drive both. I’ve looked at several online schematics but none had both functions. These meters appear to be 100ma? haven’t tested yet but a circuit than could drive both and is adjustable for different meter power might be a good addition for a RF Toolkit, I prefer analog meters instead of leds. If anyone has a working schematic for this please let me know, I’ve acquired several S-Meters over the years for various projects but would like to start using them in QRP projects.

Thanks,

Jim


 

Hi Jim,

Back in 1999, we have a Flying Pigs project to build a 10 meter xcve

https://kitsandparts.com/minipig/

It had a dual function analog meter...on for power indication and another for AGC voltage (S-meter)

For the record, I worked another 1 Watt station in Denmark back in the year 2K using this radio.

-Diz, W8DIZ


On 1/29/21 9:41 PM, James Lawrie wrote:
Hello,

Kinda of topic maybe, but I scored a few combo S-Meter and Tuning Indicator meters that appear to be for a high end Stereo and am looking for an S-meter and Tuning indicator circuit that can drive both. I’ve looked at several online schematics but none had both functions. These meters appear to be 100ma? haven’t tested yet but a circuit than could drive both and is adjustable for different meter power might be a good addition for a RF Toolkit, I prefer analog meters instead of leds. If anyone has a working schematic for this please let me know, I’ve acquired several S-Meters over the years for various projects but would like to start using them in QRP projects.

Thanks,

Jim


James Lawrie
 

Hello,

Thanks for the reference, I’ve got lots of LM358s and MC1350s and looks better than the others I’ve looked at so far. My ultimate goal is to build a Triple Conversion General Coverage receiver, I’ve managed to source several Collins 500khz Mechanical Filters from old ARC series HF Transceiver for last IF, now just trying to figure out how to make a center of envelope tuning indicator so both S-Meter and Center Tuning Meter function correctly. That’s why I’m glad your going to post the discontinued RF-Toolkits PCB files later. With those and the other hard to find parts I have it should be a lot easier now. I’m not a fan of digital parts unless used for analog purposes, but I’m sure I’ll need to go digital on VFO functions (SI-570 series or better), fun part will be trying to integrate a National Dial into a digital VFO.... 

Jim


 

Jim,

The Hybrid Cascode IF Amp is ready for public consumption.

Did you want one of those?

If so, I can add one to your current order to be shipped tomorrow.

73, DIz, W8DIZ

On 1/30/21 5:52 PM, James Lawrie wrote:

Hello,

Thanks for the reference, I’ve got lots of LM358s and MC1350s and looks better than the others I’ve looked at so far. My ultimate goal is to build a Triple Conversion General Coverage receiver, I’ve managed to source several Collins 500khz Mechanical Filters from old ARC series HF Transceiver for last IF, now just trying to figure out how to make a center of envelope tuning indicator so both S-Meter and Center Tuning Meter function correctly. That’s why I’m glad your going to post the discontinued RF-Toolkits PCB files later. With those and the other hard to find parts I have it should be a lot easier now. I’m not a fan of digital parts unless used for analog purposes, but I’m sure I’ll need to go digital on VFO functions (SI-570 series or better), fun part will be trying to integrate a National Dial into a digital VFO.... 

Jim


James Lawrie
 
Edited

Hello,

yes I had planned to purchase two or three but didn’t see them on the order form. Are these inline with the upgrades for the original Progressive Communications Receiver published in QST Nov 1981? I’ve got literally a box full of dual gate mosfets from the 3N series up through BF series and a bunch of BF998 SMTs I bought from mouser before EOL. That’s an idea too for another Toolkit, something using Dualgate Mosfets, there still out there and I’ve always been fascinated with them. I actually have the guts minus Audio and Power Supply from an old R-390A that I wanted to convert to solid state (Main Reason I started collecting them), saw a few articles on ARRL about converting others during the sixties.

Couple more questions about the 1 watters and 5 Watters design, but it might be better to ask via email instead of forum, it deals with your design and using MPSH-10 NPNs, particularly in the first SA-612 section. Are they used as RF Amps into the 612? If so do they overload? I’ve never found the noise specs for the MPSH-10s but if they work I’d be curious to try in other projects since they seem a better match than the 2N3904s, not as much power but better for RF I’m guessing.


Thanks Again,

Jim