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Just wanted to get some input about what people want in a GMRS yagi. I have been wanting to get into the yagi business for a while now and I am just getting around to building a prototype now that I have tower space to test it. This one is being made with crappy tools, the ones I sell will be...

Here is the gamma match video I mentioned in the thread I deleted asking if I should do it (decided to regardless), so here it is. Edit: considering a part 2 in the near future where we deviate from recommended values and see what effects it has on the bandwidth and capacitor voltage (since...

Stumbled across K7NS's website. There are all sorts of cool things there, some include really simple DIY zinc rectifiers and zinc negative resistance oscillators and shows a simple transmitter that uses no tubes or transistors. Shows curve traces too. There is page on a flame triode and an...

use a 7" tablet style device in a shielded (my AA170 wasn't) and outdoor-ruggedized case with rubber corners and anti-glare screen, kickstand, built in 5GHz wifi hotspot with web server for app-free wireless control, a couple dozen extra user configs/custom cals, port extensions, option to...

That 200' tower that someone stole, just saw a video from 3 days ago where some people investigated the site. The tower has been clearly missing for a years and he is on gofundme trying to replace what was "stole last week". I think brett elmore is gonna be in some trouble, not only for the...

I don't know anything about tube equipment. When I was younger, I barely knew enough to save the tubes I did come across. Now thinking that I might one day use them, I tried looking them up. Three I cannot find info on. The first two pics are a 6EW[something]. The middle pic is a little one...

My phone just rang, one of those "Spam Risk" calls. I was curious and looked before clearing the notification and the number looked familiar. Reminds me of the days you could press *#9 something something something # on a Nokia and change the number that appeared on the recipients caller ID.

Talking to a local friend while he was testing out his one week old Uniden PC 68LTX and there is a strange sound that briefly occurs when he keys up. It wasn't there a few days ago when I first heard him on it. I had him switch radios and it went away. Looking at the audio recording from my...

Just curious if anyone has ever reused it and how many times that might be possible before it loses its low mp or becomes too difficult to work with. I never knew about low mp solders until yesterday when it popped up as a suggestion while ordering solder and flux for aluminum. Of course...

I know its not really radio related, but it does transmit and receive :) On our little lake, there are some very good stories from days past. One of them was about the farmers wife who got mad and tossed his still in the lake. We figure within throwing distance of a strong farm woman, it is...

Does anyone have a schematic for this mic? Thanks!

I've had nothing but bad things to say about using these for crystal replacements, but at $2.77 a piece, I couldn't help but add a couple to the last mouser cart. What puzzles me is the excessive packaging and humidity warnings. The package sounds like it has desiccator beads rolling around in...

This took some doing, and if you ever read this Manfred, thank you for explaining some of these things to me, I'm sure there is plenty more to learn about it. When designing the output network, the most important thing to know is the transistor’s series equivalent output impedance. If you...

Let's make a board number database to aid in the search for schematics for these "unknown" radios. If you happen to peek inside your radio and see a board number, post it with the model of that radio and the year/location of manufacture if available. Some models used different boards over the...

What coax is good for scope probes? I am going to get some RG-400 to replace my jumpers, but I need something of much smaller diameter that is double shielded and flexible for homemade probes. I prefer it be 50Ω and double shielded and low loss through at least 200MHz. Does RFParts have...

Sorry this is such a big post. I watched a video about bandpass filters and I am trying to figure out the design strategy they used. In particular, how to calculate the Q of this filter. A screenshot of the filter and parts table: The transformers in the table all have similar turns ratio...

I am repairing a Cobra 148GTL (1996 Malaysia, same board as Texas Ranger 296GK, board EPT014810Z). The crystal filter is bad. I have signal going in, nothing coming out. The problem is that I only have one junk radio with a 7.8MHz crystal filter, and that is from the Teaberry Stalker II board...

The internet has no shortage of people arguing whether LMR400 is junk or not, and I am trying to get to the bottom of why because I know a few people that use it without issue (myself included). I think the issue can be narrowed down to one of four things. 1) water ingress 2) damage from too...

Where did the term "videogate" come from and why is it used so heavily when posting videos of CB radio contacts? Just curious, not complaining. No dictionary has the term, chatgpt hasn't heard of it, and searching it returns nothing but a few scandals and CB radio stuff. Did CB'ers invent a...

I am not working on a radio, just looking for a little theory. When I think of varying the dead key, I immediately think about varying the regulator that controls the collector voltage of the finals. However, i assume that if it were done that way, every time the collector voltage was...