The balloon leaks less at altitude because the pressure on the inside and the outside come to equilibrium by diffusion. The contents will leak until equilibrium is reached (if that is, in fact what

Hi Allison, I'm using the 40m lpf and the 20m lpf (positions 5 and 3 respectively). Although, I've double checked the values and the windings on the 40m filter, I've not checked the 20m one! Think

Gerry, I’m wondering what you mean by four times larger? Do you mean four times the volume? Or four times the surface area? It’s not a trick question. I’m just trying to follow your argument.

K9HZ wrote: "The balloon leaks less at altitude because the pressure on the inside and the outside come to equilibrium by diffusion." One has to consider the partial pressure of gasses. There is

In actuality, this is Backwards of what is happening with these small floaters. They are in fact miniature small "Superpressure" Balloons. When they float it

Obviously I meant 144.390 !

Here’s the math. Again, excuse the bandwidth and delete this straight away if you have no interest. This will be my last post on the subject because it’s getting old. There is no reason to

Good evening everyone Remember its the last Monday tomorrow so its the QCX party. Fun for all and conditions seem reasonable today so fingers crossed it will stay good. Hope to catch some of you on

On 5/26/2019 4:26 PM, J68HZ wrote: For an irregular shape like a baloon, you'll have to do some integration (a sphere for a balloon is a good approximation). You can

“The Balloon expands to equalize the pressure internally vs externally.” This is never true. The only way it could possibly be true if the balloon itself offered no containment force against the

In most balloons the pressure differential between inside and outside the envelope is soo extremely small that it took many many flights to try to measure it.

I'll bet my 'ticket', your backwards coil is FINE. Leave it for last. Transformers for phasing are a different issue. Extra winding (and too few) can be repaired without unwinding. Don't make extra

I had this same confusion when I first started mine up! It's spelled out in the manual, but I guess it's easy to overlook.

Just spent the last few hours scrutinising the low pass filters. Found a couple of mistakes. One choke with a winding too many, and another wound backwards(!).... I rebuilt the 20m unit just to be

European friends, please aim your 20 meter antenna toward Japan for part of the 1300-1400z session, and I'll be listening around .060. I'll also be checking 40-meters for NA same session. JS6TMW

Stephen, You are asking what this statement means: > At 10,000 meters the air is roughly four times less dense, so the balloon > will be 4 times larger than at sea level. By "four times larger", I

Hi..I'm Graham VE3WGW residing on the shores of Lake Eire in Canada. I have just built 2 of the prog rocks. Did the change of the 39k to 27k in the filter circuit to get closer to .33v. I installed

Michael, With C1, C5, C8 removed and with T1 configured for 40m RX is working well for all bands, but the lower bands (80m, 160m) are a bit deaf. So initially wind T1 for 80m would do probably better.

Thank You Jerry! Buoyancy can be a fun thing to play with! Check out this design of flight train we have flown twice, and seemed to have worked, sadly the payloads did

Hello Allison, Thanks for the reply. What we are doing is driving this modified to 4013 flip flop, pair of IXD_614 fast FET driver IC's, 1kW Class D amp direct from the Si5351a output via a 220nF