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SMF - Just Installed!

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 11 
 on: August 25, 2013, 08:05:17 AM 
Started by NW7US - Last post by N0SMX
Its a great mode.  Ive been using it for about 3 years and it gets better all the time.  Ive been running JT9 the last couple of weeks, and its awsome also.  It works wanders with very low power.  First Dx on JT9 was SV2CBN.  :)   Im running WSJT-X  V1.2 r3563      using my IC-7600 and Mosley yagi @60', but lots of verticles and dipole used all over the world with huge success...   73 and Good Dx

Dennis N0SMX
Elizabeth Colorado
DM79rm

 12 
 on: August 22, 2013, 08:09:53 PM 
Started by KB8OYR - Last post by KB8OYR
Kind of you to say, DG and I'm your yeoman in this pursuit and keep looking for the answer by trial and error; usually the latter.  In the off chance I find something, I'll share it with the group. 


 13 
 on: August 21, 2013, 08:48:44 PM 
Started by KB8OYR - Last post by W7TFO
I'm such an old-school dinosaur I never even thought about a ferrite in the works...

With them, I'm of no use.

Best,

DG

 14 
 on: August 21, 2013, 06:51:25 PM 
Started by KB8OYR - Last post by KB8OYR
Thank you for the response.  My aim is use up some of my (non-spec) junk-box ferrite torroids as chokes so I can save my good ones (with specs) for design purposes.  I don't doubt your E.E. admonitions, but, as tired as I am at the end of my work day...   How about I just wind a couple of them up and try one.  If it burns the house down, I'll try the other.

 15 
 on: August 21, 2013, 07:27:10 AM 
Started by KB8OYR - Last post by W7TFO
The choke value is not only rated in uH, but also for a resonance point, usually relative to the distributed capacitance across it.

This is why you find some RF chokes having different-sized pies wound on it: to reduce the 'solenoid' effect of a single winding at particular frequencies.

If self-resonance occurs at a particular frequency, it will cease to perform the isolation function.  If it is handling power, such as in a plate circuit, it will probably burn and be damaged.

73DG

 16 
 on: August 20, 2013, 08:02:55 PM 
Started by KB8OYR - Last post by KB8OYR
The ARRL Handbook cites many examples of broadband transformers to transfer power from one stage to the succeeding one.  It is stressed that the primary winding must present 4 times the inductive reactance of the preceding stage.  But my question is:  must the secondary winding also present 4 times the inductive reactance of the base impedance of the following stage or the ACTUAL inductive reactance of the base impedance of the following stage?

 17 
 on: August 20, 2013, 07:39:22 PM 
Started by KB8OYR - Last post by KB8OYR
Is there a problem with substituting a larger value rf choke?  For instance:  if the ARRL handbook calls for a 30 micro henry choke for a class C amp on 30 meters and I wind a....say...200 micro henry one in it's stead, would it matter?

 18 
 on: August 15, 2013, 02:04:25 PM 
Started by KE7TRP - Last post by KE7TRP
My friend ran some data on an 80 meter dipole.  The idea is NOT to cover the entire 75 and 80 meter band. The idea here is to cover EITHER,80 meters OR 75 meters with no tuner.

This would be a coax fed antenna, at 45 ft high in an inverted V setup.   I will try adding one more wire to my existing 80 meter dipole when the weather cools down. Its 110F outside currently.  In the real world my 80 meter single wire dipole with DX engineering balun has 200KHZ under 2 to 1.  More than the plot shows for a single wire dipole.  I suspect that with one extra wire attached using Ladder snaps will likely get me the entire 75 meter band under 1.5. 

Ke7TRP

 19 
 on: August 14, 2013, 08:52:33 AM 
Started by WA2ROC - Last post by KE7TRP
Looks really nice!  I had a friend who had one with the clock in it. The clock even worked. I will ask around for you.

C

 20 
 on: August 14, 2013, 04:50:09 AM 
Started by WA2ROC - Last post by WA2ROC
I replaced the NC-300 (I have 2 of them now) with a really nice Hammarlund HQ-170.  It never had a clock and I am looking for one (who isn't?)

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