I'm going to assume that the seller was confused between 30L1 and 30S1.

I have a 30L1 and basically agree with above comments re the 572B.  However I had a couple of 811's go out, and others had some age.  So decided to replace with four matched 572B's.  Bought from Penta Labs for $140.  Output power about the same, maybe 900 watts vs the 800 watts I was getting from the old tubes just before failure.  Power supply is the limiting factor, as stated above.  The 572b's I bought were made in China (same tube as the "Taylor" brand).  I slightly readjusted the phasing pot so the tune-up zero was at the correct loading.  Otherwise no problems.  Physical fit was fine.  

I wouldn't recommend anyone pulling out good set of 811's to replace, but if replacing, $140 is not bad for tubes with 2 1/2 times the plate dissipation.  Should last forever.  And my shack isn't as bright as before.

John

Almost any size wire that will physically stay up will work ok.  Even gauge 26 will have nominal resistance.  Enameled wire is hard to see.  Also 18ga copperweld, after it weathers, is good and much stronger.  Either RG58 or 59 should be a good choice.  59 might be a better match, but a low antenna might actually match 50 ohm RG58 better.

If the coax will be visible, you might even consider some RG174 for part of the length.  It has higher loss of course, but if you used it only for the visible part, and RG58 for the rest, your total loss should be acceptable.  You can also spray paint the coax with camouflage spray paint (available at Home Depot, etc).

Good luck, John

Keep an eye on the SWR.  Any abrupt change might indicate an "over-the-fence" event.  If so, running high power might be a deterent.

I am not an owner of an Emtron, but I tried.

I sent several emails to Emtron over a several month period, asking some questions about their amplifiers.  NEVER GOT ANY RESPONSE WHATSOEVER.  I figured that if they were that inept on customer service when I was shopping, what could I expect after they got my money.  So I bought elsewhere.  

I didn't need a vendor many thousands of miles away that doesn't answer emails.  

John

Jeff- if you can find an LK800C with the "TNY" upgrades (by Omega Electronics), buy it!  Great amp.  I have also heard good things about the 500 series.  73, John.

My LK800 has the filament transformer in the RF unit.  My power supply unit only has the hv transformer.  

Here is one site that has all kinds of info, graphs, etc about propogation.

http://hfradio.org/propagation.html

Also on the ARRL site, check out http://www.arrl.org/tis/info/propagation.html

I think you can go direct to this page, but if not, go to www.arrl.org and then to Support, then to Tech Info, then Propogation.

You are right, it's been bad!  Maybe better tomorrow.

John

Omega Electronics does the TNY upgrades to the LK800 amps, so Bill might be able to answer your question.  www.omega-electronics.com.

Good luck.  John

If you are looking for a photo-type card, I can highly recommend Geoff G8RCZ at www.fds-graphics.com.  Great guy to work with, very creative.  He is in England, but that hasn't been any problem at all in developing my card and getting shipment of cards to me.  If you would like to see my card go to K0IZ at qrz.com.  

Of course photo-type cards are more expensive than just text/graphics, type.  

John.

Just in case the alarm company pulls the "its your problem" answer, you might want to print off some info about FCC regulations from ARRL site.  Manufacturers have the responsibility to assure that their products are not sensitive to RF.  So failure to do so would presumably allow you to void any contract with them, and switch to someone else.

Having said that, the bypass capacitors, etc from another poster  may very well help.  Some smoke detectors are particularly susceptible to RFI.

Your 134ft is about 1/2 wavelength on 80.  So both ends of the wire are high impedance.  Your existing ground is rather RF lossy (high impedance).  So what you have are two high-impedance parts of an antenna, feeding with low-impedance coax.  I would think very high SWR.  Your length of coax is probably near 1/4 wavelength at 80 (taking into account velocity factor of the coax).  So the coax is transforming the high impedance down to something your transmitter can deal with (ie one end is high, 1/4 wavelength later it is low).

As someone else has mentioned, I would add some ground wires to reduce the ground loss.

Your antenna is already unbalanced, so I don't think a balun would do much for you (is so far as converting balanced to unbalanced).  You could consider a 4:1 to transform the higher impedance down closer to the 50 ohms.  Do this at the antenna, not at the transmitter.

In addition to the various ARRL antenna publications, also check out http://www.cebik.com/radio.html for some good info.  Good luck.  John.

National code requires both grounds to be connected together.  This prevents (minimizes) a voltage potential between the grounds, and your equipment.

But you should not connect the ground rods to the house wiring (neutral ground) at an outlet since code also specifies only one ground.  So to be correct you do need to run a wire (even if long)from your antenna ground rod(s) to the service panel, and connect at the same point in the service panel as the existing service panel ground wire.  

I doubt that most hams connect both grounds, but that is the code.

www.polyphase.com has good info about lightning and grounds.

John.  

Might I suggest an alternative to building:  Check on eBay for some Bird brand dummy loads (do a search on "Bird dummy".  They are available in various wattages, rated continuous duty.  Based on my experience you can safely run 2 or 3 times their rated power for periods up to several minutes.  I have a 500 watt bird that I have run 3000 watts into for about 1 minute with only small temperature rise.

The Bird units are super on SWR, typically flat to 1GHZ or more.  MUCH BETTER than any loads being sold, and much better than what you can make yourself.

I have seen various Bird units for sale with ratings of 10Watts, 20, 50, 100, 500, and 1KW.

Radio Shack coax, UGG!  Get some good coax with good braid coverage (95%) from a regular ham supplier.  LM400, RG213, etc.  Don't get 9913 as you will have a problem with water.  9913F is ok.  I like N connectors as they are more waterproof compared with PL259 type.  But if your antennas use the SO239/PL259 types, make sure you waterproof the connection(s).

Make sure we are talking about same thing - might you be referring to "hammertone" finish?