MiniBar Kits Are Now Available

[@brentjohnson6654]

Hi Tom, I am just popping over here from the CaHR stream you were on for fuses. Excellent conversation on that and crowbar protection circuits. I am a retired electrical engineer and who thought I would see such familiar things from my career. All the best from north Texas. 73 de KI5HXM

[@dovetomarc]

Thanks Tom. I just ordered. A request…Any chance you can do a short “assembly demo” on how to put the kit together. Thanks.

[@HamRadioA2Z]

Hi. Thanks for your interest, and your order! The assembly is pretty simple, but I might put a short video together.

[@Chuck1855]

I watched your video about this awhile back made me want to build 2 for myself. Several club members are interested in doing this as well.

[@davidfairchildg0ddf628]

Great to see that you now have these as kits Tom, competitively priced too. A great addition to the shack to protect expensive dc equipment.

[@TonyLing]

It must be very reassuring to have one of those at the rig end. Great job Tom.

[@K5YVY]

Thanks Tom, I been waiting for these, I just ordered Two!🥳

[@HamRadioA2Z]

Thanks!

[@MikeN2MAK]

Looks good! Thanks, Tom.

[@robertmeyer4744]

great circuit to have. many power supply's do not have them bult in. just the basic board can be hard wired inside the supply. Love the SCR . I have them from a few amps to 2200 amps. the 2200 amp one called the hockey buck is bigger than a real hockey puck. I have been fixing linear power supply's many years. started in like 1976/77 . high voltage is common failure. some Astron came with out crowbar but they sell a small board to add that . loved your show on Coffee and ham radio . The Busman I normally use have a UL on them. a good fuse is best for that board. Busman and little fuse both sell breakers that plug into same holder. 2 types . auto reset and manual reset. I would not use them in ham radio. 73's

[@HamRadioA2Z]

Hi. Thanks for the comments!. Years ago I worked for a forklift company that used SCR based drive controllers. We used some of those hockey puck SCRs.

[@TheSmokinApe]

Fantastic work Tom, these look great 👍

[@HamRadioA2Z]

Thanks Ape! Starting simple. More to come.

[@pcfreak1992]

Awesome project, too bad I can’t order it to Europe apparently. Are you planning on offering international shipping at one point?

[@TonyLing]

It's a shame that the few amateur radio outlets we have in the UK don't procure more modules and kits like this.

[@HamRadioA2Z]

Hi. Yes, I do plan on international shipping. I just need to make sure I've got all the logistics and rules sorted out. Should be up and running soon.

[@Jed-q2q]

I have been looking forward to your mini-bar!

[@daveN2MXX]

Have you tested these in the presence of RF at different frequencies? Could common mode or ambient RF cause the zener to bias or the scr to unexpectedly trigger?

[@HamRadioA2Z]

Hi. It's a good question. I don't have the EMI test equipment needed to inject controlled RF fields or levels into the circuit. Part of the purpose for the 0.1uF capacitor, C1 is to shunt spikes and RF noise to ground to help prevent false trips. If someone has RF noise tripping the crowbar, it would need to be handled in the same manner as RF in the shack causing any other electronic misbehavior. RF chokes and other measures would have to be applied to coax and other cables coming into the shack to supress the noise before the circuit.

[@stirlingpark6145]

Thanks. No shipping to England yet?

[@HamRadioA2Z]

Hi. Not yet. Sorry. I’m trying to get all of the duty, tariff & logistics stuff sorted out for international shipping. I will keep you posted. Hopefully setup soon.

[@cliffbarrimore]

Interesting device, unfortunately my car, BMW, can charge at over 15v, especially when the regenerative braking kicks in, all my radios have not had an issue with this voltage, but I would be interested in one of these if the the cut off was adjustable between 15 and 16v. I believe all the radios I have are rated to 16v, although I would like to cut out at 15.5v

[@HamRadioA2Z]

This is good to know. I believe car charging systems are one of the more common causes of rigs getting fried (Failed regulators and >>16V, not hybrid systems). I didn't think about some of the mild hybrids regularly hitting voltages >15. I have a future, higher-end product in mind that should be compatible with your BMW, but still provide protection. Stay tuned...

[@cliffbarrimore]

@@HamRadioA2Z Mine is actually just a diesel not hybrid, I am sure hybrids do the same, mine does regenerative braking and puts volts into the main battery.. I'll keep an eye out for future revisions..thanks ZL1CTS

[@KS0JD]

Nice design Tom! 73

[@HamRadioA2Z]

Thanks Jeff!

[@Chuck1855]

Do you offer a quantity discount if you buy 10 or more.

[@HamRadioA2Z]

Have not considered it yet. If these become popular enough to warrant a larger production run, I can probably do something.

[@virtualhermit]

How many carbs, sugars and fiber?

[@chopchop3464]

Atkins designed

[@HamRadioA2Z]

These are the 0 carb version. 😁