Home |
Search |
Today's Posts |
#26
![]() |
|||
|
|||
![]()
On Mon, 24 Mar 2008 04:32:39 -0700 (PDT), Artem
wrote: I've observed that, and I have observed it is not enough from your photo - if you still have self-oscillation. Your pictures do not reveal any choking of the RF Out cable. It's inside. Nearby BNC socket. Which defeats the choking. As for the diagonal arm for "ground." This is fine insofar as it being placed in the electrical middle of the antenna loop (a ground), but all this rat's nest of wiring throws the concept of balance out the window. I think that some disbalance should compensate differencial amplifier on transistors. That makes no sense whatever. another invitation to problems when a 9V battery would solve that too. Local power would discard the need for the ground Yes. But FETs draw more that 10ma each. That is trivial. However, you can bias for less because you don't need that much drain current. coming from the loop's perimeter, eliminate unnecessary AGC, reduce the complexity of choking, lower gain (it obviously has too much), and give you only one coax coming from the antenna. Cable length is not problem. I'm living in apartment. I can put antenna outside the window. But not on the roof. I can make power supply over coax cable. I can put Atmega8 (en example) to amplifier and add DACs for operate varicaps, AGC. I can add rectifier and filter for detect self-oscillation and automatics reduce AGC. But it's not necessary. Sounds like a lot of unnecessary complexity. The one thing you repeat is varicaps, but I don't see them. 73's Richard Clark, KB7QHC |
Thread Tools | Search this Thread |
Display Modes | |
|
|
![]() |
||||
Thread | Forum | |||
About a narrow filter at 10.7 MHz | Homebrew | |||
Narrow Band FM bandwidth and channel spacing | Equipment | |||
Flower Pot Antenna a Dual-Band (20m and 10m) 'portable' Antenna | Shortwave | |||
Narrow & Wide............ | Shortwave | |||
Antenna Specialists MON-4 VHF Low Band Scanner antenna - Can I trim it for 6 meter use ? | Antenna |