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31
General discussion (QSO) / Re: FM Beginnings
« Last post by K3DAV on August 02, 2013, 08:24:13 PM »
That's a great article on Armstrong.  I am a big fan of him.

I also did a nice tribute article about this great man on my website.  Here is the link...

http://www.k3dav.com/edwinhowardarmstrong.htm
32
General discussion (QSO) / FM Beginnings
« Last post by kg7ddl on August 02, 2013, 09:34:46 AM »
A bit of history on Edwin Armstrong and his tragic end.
http://www.liveleak.com/view?i=226_1375413795
33
FOR SALE / FS Elecraft K3 & P3 $1900 Icom IC-756 Pro 3 ac6pt@yahoo.com
« Last post by ac6pt on July 31, 2013, 12:43:06 AM »
It comes with the following barely used set:

original Icom IC-756 Pro 3 a fused DC power cord,
original unused HM-36 hand microphone,
operations manual, schematics,3 fuses, 1 ¼” plug for a CW key,
installed UT-102 Voice Synthesizer Unit that announces frequency, mode and S meter level.
Icom PS-125 power supply with original box, SP-21 Speakers and MFJ-392 headphones with original box
Asking: $1250 shipped worldwide
Email: ac6pt@yahoo.com
Phone: +1715 544 3126



FS Elecraft K3 & P3
Loaded K3/100 with P3 Pan adapter
List of set:
K3/100
KAT-3F_______100 Watt Auto Tuner (internal)
KRX3-F_______2nd RX
KBPF3________General Coverage RX Module
KDVR3________Digital Voice Recorder
KTCXO3-1_____TCXO (0.5 ppm)
KXV3A________RX Antenna, IF Out and Xverter Interface
KUSB_________USB to Serial Converter
KFLA3A-1.8K__1.8 kHz 8 Pole Filter (2 pieces)
KFLA3A-2.8K__2.8 kHz 8 Pole Filter (2 pieces)
KFLA3A-250___250 Hz 8 Pole Filter (2 pieces)
KFLA3A-400___400 Hz 8 Pole Filter (2 pieces)
KFLA3A-6kHz__6.0 kHz 8 Pole Filter (2 pieces)
P3-F_________Pan adapter
Warranty is transferable

Asking: $1850 shipped worldwide
Email: ac6pt@yahoo.com
Phone: +1715 544 3126
REYNALDO
34
AM Transmitters / P&H Audio compressor AFC-2 REHAB
« Last post by KE7TRP on July 30, 2013, 05:36:04 PM »
I got this sweet P&H vintage Tube audio compressor recently and plan to rehab it this weekend.  The AFC2 was made in the 50s for ham radio use.  It features an AVC compressor and selectable Audio bandpass filters.  A neat feature of the AFC2 is that it has LOW and HIGH impedance inputs and outputs. So you can use any combination of low or high microphonium and low or high OutPOOt. 

Here are the pics as received.  I removed the tubes and ordered the capacitors so far.  I will replace the caps and install a 3 wire power cord. I also plan to clean the AFC2 to like new condition.

I will likely use this with a vintage EV664 mic and then into the Johnson 500 transmitter.

C
35
Digital Modes / Re: Digital Ham Radio
« Last post by K5TPK on July 29, 2013, 06:19:12 PM »
I've played around with the digital modes for a couple years. Mostly a listener, because I'm a terrible typist for live QSOs. I'm using a USB SignaLink with an FT897D. I use DM780 and FLDIGI software. FLDIGI is mostly used for NBEMS functions. There are NBEMS NETS on VHF/UHF and HF. There is also weekly test transmissions from Voice of America using AM on HF and the FLDIGI software. Check out www.VOAradiogram.net for details.  Bottom line... Lots of fun!!  :)
36
Antennas / Re: Double Bazooka antenna plans
« Last post by KE7TRP on July 29, 2013, 11:33:34 AM »
37
Antennas / 40 meter Double Bazooka Vs 80 meter ladder line fed doublet
« Last post by KE7TRP on July 28, 2013, 11:58:26 AM »
This test is a 40 meter Double Bazooka wire antenna made from RG11 coax VS an 80 meter open wire line doublet.  The Doublet is from Trueladderline.com and uses 600 ohm feedline. The antenna is hooked to a Johnson KW matchbox balanced tuner. The Doublet is at 40 ft.  The Double bazooka is at 30 ft.  The DBZ has a lot less noise with stronger signal than the Doublet.


I took this video today.

http://youtu.be/_nWCGKyOSqk

38
Antennas / Re: Double Bazooka antenna plans
« Last post by KE7TRP on July 26, 2013, 10:19:34 AM »
I got the 40 meter DBZ installed.  I compared this to my 80 meter open wire line fed doublet yesterday. Both close to same height.  On 40, The 80 meter open wire line antenna has gain.  About 3 DB according to EZnec. I am using a Johnson KW matchbox with the open wire line.

Base line noise level is approximately 4 to 5 DB lower on the DBZ. I used my SDR pan adapter to show the static noise at various frequency's across the band.   

Peak signals from Foreign Broadcast where exactly the same. I could not prove one was better than the other. I then proceeded to make a page of 40 meter contacts across the US. Not one station reported one was better than the other.  I could switch between words with NO delay.  Over the course of the day, stations just reported that they are the same.

The SWR on the analyzer shows 1.0/52 ohms at 7200 where I set it.  Its under 1.5 across the entire 40 band.  No tuner needed.   

The 40 DBZ does not come over the Home theater.

Looks like a great antenna for 40 meters.

C
39
Antennas / Re: Double Bazooka antenna plans
« Last post by KE7TRP on July 25, 2013, 08:57:26 AM »
Thanks for posting Paul. Yes, We do not have an antenna range. I wish we did. However, We can compare antennas at home.  That's a great part of the hobby that I enjoy.

I only had one antenna up at a time.  The second antenna was in a pile under the tower between tests.  I tested 4 times back to back.  In all cases, my chart has reports of higher signal on the DBZ. My Chart shows higher RX signal that is in line with the gain in TX.  I would not have believed this if I was not there.  It really makes no sense to me as the Open wire doublet should have next to no loss through a balanced tuner.  However, There must be some loss somewhere or the patterns are such that in state contacts suffer on the doublet. 

I think once I do my tests over a 2000 mile distance, we will have more data.  Its possible that the Doublet has a strong vertical component.  If so, Then this all makes sense. The close in under 500 mile contacts are going to be better on the DBZ.  More of an NVIS pattern.

Using a Field strength meter at 25 watts AM carrier there is no detectible RF on my Feedline of the DBZ. On the OWL, of course the meter pins near the feedline.  I have current meters on each leg of the doublet and It is in balance with in a % or so.  Even then, You do have some RF off the OWL.

The DBZ does not come over the home theater which is a great plus in my household.  I think this is because the DBZ is not radiating over the feedline and causing the interference.  There is also the idea that the OWL with balanced grounded tuner, Is using the HOUSE wiring as a counterpoise.  Hence, The home theater turns into a public address system.

I was going to run some more tests today but woke up to pouring rain.

C
40
Antennas / Re: Double Bazooka antenna plans
« Last post by W5LZ on July 25, 2013, 06:46:30 AM »
Most of the 'playing' with a bazooka antenna was before 'eHam' or the other review sites were around so I can only go by what I've read and experienced.  Almost all of that 'testing' was done on 80 meters, that's where I hung out, and there were others there that used a bazooka type antenna too.  I have to say that this sort of 'testing' was subjective, not objective in nature.  I certainly didn't have the equipment and antenna range to do a really objective type of test.
Antenna comparison testing is very difficult to do objectively, there are just a huge number of variables involved in that and they can 'go' either way good/bad.  'On-the air' testing has got to be one of the most unreliable means of testing antennas.  What if there's no one listening, what if there's too many listening?  Anything around an antenna can affect how it behaves, so how can you have two antennas up at the same time, on the same band, and they not affect each other?  That doesn't mean that I doubt what you experience doing this sort of testing!  It does mean that it isn't exactly a 'take it to the bank' sort of test.  It's subjective.
If a particular type/style of antenna works for you then by all means use it. 
 - Paul
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