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Why is all the ham SDR for HF?
I think because thats where the market is. (demand)
But for VHF/UHF SDR, you need to go where the students and researchers go.
Such as my Ettus SDR box, for which I put the RF board which covers 64MHz to 2.2GHz.
It will do any modulation that the software...
If you're running on a single band, A dipole would be better than a screwdriver.
Screwdriver requires a counterpoise, some big metal sheet. Cookiesheet?
Or just get a 102"whip and mount it on some piece of metal like that if your only on 11/10m.
A magnetic loop is probably the best antenna...
Sure, there are some welfare abuses.
But its small potatoes compared to our military budget: We spend as much on military as the rest of world combined.
This is unsustainable to have such large military spending while simultaneously keeping taxes on the rich at such historically low levels.
A copper board such as that is not "one big ground", unless it has plated-thru vias at regular intervals.
For some perspective: a 4inch piece of 20AWG wire has 6ohms of inductive reactance at 27MHz. (at Inductance of a Straight Wire: A Calculator)
Braided wire has lower inductance because of...
The braid is there precisely because the board is one big copper board.
Meaning the board has no plated-thru holes to the bottom layer, also known as "vias".
So because of that, there is insufficient ground connection between the pills and to the (-) power lead, which is compensated for by...
The efficiency is horrible, if it needs 300A at 20V, that would be 6kw.
For 1kw out? that would be 16% efficiency.
ok, if its 2500w pep then you still dont have more than 40%.
Those new pills from NXP or freescale are at least 70% efficient.
Indeed, with devices such as MRFE6VP61K25H that operate up to 600MHz.
We should be talking about running a kilowatt on FRS instead of "noise toys on FRS".
Freescale and NXP are at the top.
ST, Microsemi and M/A COM are runner's up, but still good parts.
Toshiba doesn't do any RF power...
Its already been done on 40 meters, using HAARP.
Moonbounce‏ - YouTube
However, this HAARP site can have effective radiated power in the billions of watts.
Yet, it should be easier on 11 meters, considering its closer to VHF.
Take any 6 meter EME setup that works, and size-up the...
Maybe what you call a "box" is whats known elsewhere as a pick-up "bed".
You should also try a strap between cabin and bed/box.
Often such vehicles have cabin and bed on rubber mounts, and they only have minimal DC connection between them. And for 27MHz, its like no connection.
Sure, you now have complete radio on chip, such as freescale MC13260.
But you're never going to shrink an antenna for HF bands and still have it efficient.
The RF chip in smartphones operate on UHF, where antennas are small.
The bandwidth of signal is relatively wide, so not as much concern...
Borrow a dummy load that can handle the watts from your amp.
Try it instead of your antenna.
If you still have squealing, then probably you have a bad coax shield connection.
But if you dont have squealing any more with dummy, then you likely need a few ground straps on your car chassis...
Any capacitor directly exposed to vehicle voltage should be at least 16v.
Probably (hopefully!) those 12v caps are not used for that.
good design practice actually says a capacitor should have double the voltage rating of what its actually going to see in service.
More important is what...
The frequency drift on SSB doesnt bother you?
you must be ok with adjusting the clarifyer now and then.
maybe its hit and miss.
probably the only way to be sure is to put it in a temperature chamber.
Did anybody answer it in simple terms?
Take an example of the fact that power utility company drives mostly an inductive load because there are lots of motors that run on electricity. So sometimes you will see capacitors on utility poles or substations to cancel out the inductive load.
If...
NXP just one-upped on freescale:
NXP puts the 'extreme' in extremely rugged LDMOS transistors
You can see them in the video, abusing the device under the most extreme conditions without damage.
Gone should be the days of blown devices due to broken coax or damaged antenna.
"vastly superior" industrial product might be over-stating it.
More importantly, Connecticut senate approved pot decriminalization by just one vote.
Where possession of less than half ounce only results in monetary fine.
Hopefully more will weight the costs & benefits of keeping it...
Thats the truth.
Take for example Ameritron ALS1300, with power supply just barely capable of supplying the required current.
In any case, current limiting on power supply is required. Firstly and foremost, to protect the power supply, but if you rate a power supply with double capacity you...
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