Notices by ftg (ftg@mastodon.radio), page 2

@jmorris
.086 something maybe?
No wait, that's hardline, not semiflex like this?
RG-40something?!

And agreed, Excellent antennas!
WA5VJB is a wizard pulling such nice performance from FR4.

Whoops.
Apparently we left ping running for about 428million milliseconds.
Amazingly not a single lost packet.

Fixed the radio clubs lab logperiodic.
One of the mat least.
This used to have a badly soldered piece of UT.141 coax on it.
Now it has whatever this thinner flexible stuff is.
And it is soldered properly and an effort was made to keep the transition really short.
Tho likely still crap on 10GHz.

The badly soldered .141 coax broke off one of the radio clubs test antennas. So I fixed it more proper with more appropriately sized coax.
Pigtail used was a random one from the radio clubs "SMA pigtails"-drawer.

Nice antennas with nice and flat gain too.

#ghz_bands #hamradio

@lizakowski
As a stand so that it's not on desk level.
That's more or less it

Absolute dumbest test setup.

#10GHz #ghz_bands

Definitely not the best setup, but enough to show me that this thing covers the upper edge of the 10GHz hamband well.
10.368GHz was a bit in the slope.

Something for the project pile.
This is way too mad to not try at some point.

More than a little bonkers idea and likely not very usable.
But it looks so simple and tempting.

#10GHz #homebrew #microwaves #superregen #RegenReceivers #hamradio

Source article:
https://www.worldradiohistory.com/Archive-DX/VHF-Communications/VHF-COMM.1997.1.pdf

Worldradiohistory.com sure does deserve a lot of love for preserving tons of good ham magazines from back in the day.

73 Hamradio, VHF Communications, "HAM RADIO" and so on.

Yaesu FT-817 at full power on 2m upper sideband.
3kHz RBW, 2Mhz span, max hold and me talking to the mic for a moment.

The spurs look bad, but seem to be -67dBc and -62dBc down.

#hamr #hamradio #yaesu #ft817

@synx508
Yeah.
And I was advice ages ago that FT-817 should not be amplified, as while it was compliant with regulations, it was not the cleanest of rigs.
Stuffing 160m to 70cm in a box of that size and including 8x AA internal battery means that some compromises likely had to be made.

Improperly stored AN/UPM-84 military surplus spectrum analyzer is not having a good time.
It covered 10MHz - 40GHz.
N connector input up to 12GHz, then waveguides up to 40GHz.

Yeah.
The dial ends at 40.88KMC.
And there also ends this thread.

Klystron oscillator with a big cavity in a trashed spectrum analyzer.

@jmorris
Normal copper tape on a piece of transparent plastic.
If we could get random indium bits as donations at the radio club we would not make Vivaldis from it!

Friends quick antenna build.
copper tape and some plastic as the substrate.

Remember that 100W 30dB attenuator I BBQ'd by running a 15W radio into it in reverse?
Well it looks like this on the inside.

No wonder the wrong side did not survive even 15W.

There was also this thing on the high power input trace in it.
I guess that was done to push it closer to the 4GHz spec of this thing.

How's that for some snowflaking?

And no, the cavity did not have any RF absorber.

Inside an old 7GHz DRO oscillator brick.

From top to bottom:

- Varactor for fine tuning, my guess it is used as part of a temperature compensation loop here. Lightly coupled to the DRO.

- The DRO puck inside it's glass prison.

- Coupling loop for the oscillator and the oscillator transistor.

- Output isolator, made from a circulator with one port terminated.

- Output port on the left side.

-20dB dB sample of the oscillator output signal.