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Thanks for the taping idea for the black housing of the loop. That would probably be the last resort! The loop will be exposed on the balcony in this continental climate; the tape would probably

Slick Idea! Don W4BWS -- Dr. Don W4BWS

Ooooooo. There's an idea. Teflon tape!

Why not tape it with the required colour?

Hi All: Before moving to an apartment with balcony, where the MFJ loop will stick out like a sore thumb, I need to paint its black ABS housing white or another light color. MFJ advise us not to use a

This may be interesting for LW and VLF/ELF work. I suspect that above 1MHz other effects and non-idealities swamp the common mode rejection ratio of the amplifier. 73, Mike

I found that file in the group files section. The title is: Active Antenna Amplifiers for Low Voltage Operation RevA.pdf Although the designs are for low-voltage operation, they can be used for supply

Active AM Antenna With Twin Coil Ferrite by C. Crane Co. http://www.ccrane.com/antennas/am-antennas/ JLKolb?s antenna links including the KRS AA-1 Active Antenna schematic, antenna preamplfiers,

If you have a link relevant to the group, please post it in the Links section. If you just put it in a message, it will get lost in the shuffle after a few days. The coverage of the list is pretty

When I measured the batch I got I built a buffered VCO with the L.O. coil from an old MW radio using a socket for the varactors to test the frequency output at 12 discrete voltages using a 12 position

One other problem with varactors is testing. The loop design I published in the National Contest Journal cannot be tested with the MFJ-259 impedance meter (and probably similar units) because the

I've been using varactors for MW and LW loops for years. There are a couple of things to be careful of. When using a back to back configuration I've found it best to match them as closely as possible.

I'll look at that later when I have a WiFi connection. The loop antenna is best viewd as being a current source with a series inductance and a low series resistance. When seen that way, series tuning

Yes, that's the circuit. http://www.lowfer.us/k0lr/bal-pre/bal-pre.htm http://www.lowfer.us/k0lr/bal-pre/bal-pre.htm. I thought the point was to have such a high impedance that the loop/inductor was

Is that the one with the balanced MPF102 input stage and a balanced 2N2907 output stage? I have reservations about that approach as the low impedance of a loop pretty much dictates a low input

Wow answers from the living legends themselves! I have a few of your documents in my files that I have been educating myself from! The balanced (differential) preamp I am gathering parts for is from a

Varicaps definitely can rectify and create QRM from strong signals, be they AM BCB stations or nearby ham stations or if you are running SO2R. The back to back configuration helps but you can still

> >Hi all, I'm experimenting with various remotely tuned open air loops and ferrite loopsticks. I have made >a remotely tuned varicap diode assembly and a remotely tuned variable capacitor assembly

Hi all, I'm experimenting with various remotely tuned open air loops and ferrite loopsticks. I have made a remotely tuned varicap diode assembly and a remotely tuned variable capacitor assembly (using

Applicable to receive loops? http://edn.com/design/analog/4430051/Differential-amp-has-6dB-lower-noise--twice-the-bandwidth Discuss...