Topband: what does it take to get on new band 600 meters

[Eric NO3M]

Quite a loaded question... for every 10 guys on the band, there will be 
20 ways they went about getting on (including some things going up in 
smoke and fire).

Power requirements depend on your antenna's efficiency... for an 
explanation of EIRP, see here:

http://www.472khz.org/pages/technical-topics/eirp.php

Using the formula method, you'll need to model your antenna to figure 
out it's radiation resistance.  Unless you know your local ground 
characteristics to get an accurate model, assume a vertical has 4.77 dBi 
gain, which is a gain factor of 3, in the calculations.

As for an antenna, most put up a vertical (inv-L, Tee, etc.) with some 
form of top-loading and coil to resonate it.  Lots of ground wire helps 
mitigate ground losses.  Lots of top-loading helps reduce the required 
inductance to resonate it and reduces coil losses. Construct and mount 
coils for high-Q and minimal stray coupling. But if you understand EIRP, 
it's not necessary to go crazy with height, top-loading, radials, etc., 
since you can just increase transmitter power.  It all depends on 1) how 
much power you can generate, 2) how much you are willing to waste, 3) 
are prepared for obscene RF voltage at the base if using a lot of power 
into a very short vertical (this means a good insulator, NOT cheap 
PVC!).  Guys in backyard lots can be just as loud as someone with a 
200ft (max height) top loaded vertical... again, it all comes back to EIRP.

Transceiver can be just about anything if you use a transverter, 
otherwise, something like the TS590, K3S, etc. can natively operate down 
there.  SS amp.... tube amp.... etc, etc, etc.  Of course, you can also 
homebrew something from start to finish.  Some guys are using lashed 
together setups with signal generators, etc.  There are also vintage 
Navy and other rigs that can go down there... old 500kc type stuff.

Don't forget an RX antenna... sure you can get away with using the TX 
antenna, but you'll be missing out on a lot of stuff.  Loops, EWE, 
beverages, BOGs, vertical arrays, etc....

I've been QRV on 630M since 2012 under both the ARRL's group Part 5 
grant (WD2XHS/46) and my own grant (WG2XJM).  I've used a number of 
different configurations over the years, but currently have a 67ft. 
vertical w/ 8 top-loading wires over 22,000 ft radials.  K3 to a 
transverter with dual RX channels for diversity and a 100W SS amp. I did 
modify a SB-1000 for 630M, but no longer need it.  For RX I use my 160M 
broadside beverage arrays and a dedicated full-sized 630M 8-circle BSEF 
array (1150ft diameter).  Some links:

http://no3m.net/antennas/630m-antennas/
http://no3m.net/antennas/630m-8-circle/
http://no3m.net/shack/630m-station/

I have also homebrewed a bunch of antique style gear for down there, 
including a 1930s rack transmitter which I use almost every night:

http://no3m.net/2017/10/1930s-rack-transmitter/

For general info, technical articles, and daily activity updates, see:

http://www.472khz.org/
http://500kc.com/
http://njdtechnologies.net/category/630-meters/

GL CU 630M
73 Eric NO3M



On 11/02/2017 01:34 PM, Kevin Adam wrote:
> What does it take to get on 600 meters radio antenna transceiver  power requirements
>
>
> N9IWW
> _________________
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