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Display freezes buttons and encoders stop working. Do you have some extra Audio Hat extender boards? I would like a few. Tim W4YN

Sorry Phil, I have no idea now. Never bothered keeping records. Should have as there seem to be muliple versions. I just ordered the 5" in the minimum configuration suggested on the group. Glenn vk3pe

*** I had to look that up. How can a big square have the same resistance as a little one? It's because as you add length - increasing the resistance - you also add width - decreasing it. - Jerry,

The resistance of a flat surface is called sheet resistance, measured in ohms per square. Not square inches or square cm, just per square. After that, it looks like things get complicated. The amount

Copper tape is one of the better ways to shield. Solderability is a feature you won’t get with aqua-dag or silver-dag, and these paintable solutions are quite costly, meant more for small areas with

Hey Tim… when you say it shuts down… what do you mean? The signal stops or the power goes off? Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ Owner - Operator

My bad I had left off Jumpers 18 and 19. I can now rx fine, but only for short period then it shuts down. Not up long enough to do RX calibration. Tim W4YN

** Yeah, the attenuation for the cheap carbon stuff doesn't look too good around 20M. I bought a roll of self-stick copper tape that claims that their adhesive is conductive. I figure I can put that

Have a look at msg #5998 from Chris Corcoran… He shows a number of plots that show the resistance of the coating. You can use that to figure out the attenuation for the coating. Dr. William J.

Hmm - at 14.2 MHz with the gen set to -72dBm ( as low as it'll go without an external attenuator ), I'm seeing just a hair under S9. Not bad! 7.2Mhz - just a hair under S8. Well, on that band the BPF

I didn't say that right. The calibration of the s-meter sets the ZERO point (well... -73 db point) on the meter. That is the intercept of the equation for "S" units. You also have to calibrate (eg

Yeah and make sure you do it with the attenuator at ZERO! THEN go ahead and calibrate the RX attenuation control. Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ

I am probably oversimplifying something I may not fully understand but is there a general rule of thumb for knowing if a material may be suitable? ? Such as if it measures x ohms per square cm or

Yeah… we need a calibration procedure for this too… Looks like you have volunteered Jerry! Dr. William J. Schmidt - K9HZ J68HZ 8P6HK ZF2HZ PJ4/K9HZ VP5/K9HZ PJ2/K9HZ VP2EHZ Owner - Operator Big

I was just doing this for one of my other radios, and wondered: Is the S meter display on the T41 calibrated? S9 is defined as -73dBm, or 50 microvolts @ 50 ohms. I think I'll try it out with a signal

That is on the “TO DO” list. Since this is an open/ community project… I would ask that someone with a working radio… please step up… do this as a contribution to the project if… people

I see lots of test points on the RF board, is there a list of expected voltages and signal data for each point somewhere? Trying to trouble shoot my RF board issues. Tim W4YN

I’ve never had noise from an on-board source, but that doesn’t mean it couldn’t happen. There is probably a solder bridge somewhere that is causing this… but keep it simple… to hone in on

I suspect you could spray a cheap clear coating over the top with no degradation of the graphene coating to solve the transfer problem. 20 Ohms is very low for a paint-on coating. The silver coating

I have checked adhesion to PLA+ with Rustins and it adheres very well. I was very surprised by the conductivity which was around 20 Ohms for 35mm x 35mm surface area. I would add that the graphene