On 5/18/21 9:02 AM, Jason wrote:
On 5/18/21 1:49 AM, Phil Allison wrote:
Â* Ralph Mowery wrote:
---------------------------------

A short antenna on the SA would probalby give enough signal to see what
is needed.

**Â* Best a safest answer & "short" = about 100mm.

Either that or a single loop around the co-ax feeding a dummy load.

The SA needs to see about 100mV at 30MHz to stay clear of spuriae.


.....Â*Â* Phil


Tried the loop around the coax, just a prior loop I had made up one time
for RG-8 (this is RG-58 I'm using now).Â* It's not tight around the RG-58
of course, but output stays well within the analyzer limit.Â* However,
harmonics vary depending on where I move the loop.Â* Maybe I should make
a tight single loop around the coax?

Ok, as I already had a 20:1 voltage divider, which brought levels down
to 10 dbm, I simply added another one in series. I've been testing out
a TinySA handheld unit about the size of a cigarette pack. After
watching some videos on it, it is recommended to keep levels at -30 dbm
to prevent false spurs and harmonics. My voltage divider added in
series does just that at just under -40 dbm.

Here's a question I can't seem to find the answer to: what are the
harmonic emission requirements for spectral purity for HF radio
transceivers in the US? I *think* its either -30 or -40db below, but
it's been years since I've used these transceivers. Thanks.