Re: MagicBox


Jim Kortge
 

On 5/10/2013 7:04 PM, Glen Hazen wrote:


I have a MagicBox that appears to function as designed but has one
problem. Am using a SDR 40 receiver and SAXVO. Am using an MfJ versa
II tuner with a 40 dipole. When I use the Magicbox for xmitting I get
very little power shown on the tuner. When I connect directly from the
SAVXO to the tuner I get 1 watt out and the output is variable with
VR1. I am suprised that I would see that much RF from the Saxvo.
Anyone have any thoughts on this MagicBox problem? Thanks Glen, N8WE
Hello Glen,

First off, I need to know if you put the auxillary Low Pass Filter on your SAVXO before using it directly on the air? There is a document that I did a while back addressing that issue. I've attached it to this email, but not sure it will make it through. If not, you are radiating numerous harmonics and running an illegal transmitter. Also, my guess is that the 1-watt power lever you are seeing is very bogus; the SAVXO barefoot only puts out about 200 milliwatts, if I remember correctly.

I don't think there is an issue with the MagicBox either. Above 30 MHz, the power output falls off rather dramatically, and in fact is down a few dB at 30 MHz, but that was the best I could do with the components available. My guess is that the MagicBox is filtering out some of the harmonics and you are not seeing their contribution to the overall power you see when that device is not in the chain.

Questions?

72,

Jim, K8IQY

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