View Single Post
  #119   Report Post  
Posted to sci.electronics.repair,rec.antiques.radio+phono
Michael A. Terrell Michael A. Terrell is offline
external usenet poster
 
Posts: 12,924
Default Why should someone replace ALL the capacitors on old Tubeequipment?

Clifford Heath wrote:
On 15/02/17 09:51, Ralph Mowery wrote:
In article ,
says...
Have you tried Software Defined Radio? Free software and under $10
for the USB based hardware will get you started.

I have been playing with them for about 2 years. They seem to work very
well and depending on the one you actually use, they go from about 25
MHz to 2 GHz. The sensitivity for them is about 1/2 of a microvolt for
FM. The things that can be done and free software is amazing to me.

The do all the common modes of ssb, am,fm, cw, and some other things
such as decoding pagers and even the transponders on airplanes.

Here is a link to some more info on them.

http://www.rtl-sdr.com/about-rtl-sdr/

Look for some software called sd sharp while you are at it.


The weaknesses are intermodulation due to insufficient RF band-pass
filtering, and quantization noise due to insufficient resolution in the
A/D converters. RTL2832 has ENOB of around 7... hopeless.

There's no escaping the need for a proper RF front-end for any serious
work.



Or for good RF test equipment to design and build it. I replaced my
old Boonton 42B and 92B analog meters with their 4200B and 9200A digital
meters. I also have a Fluke 8920A digital True RMS meter that works to
20 MHz. This is some of the same type of equipment that I used on the
production floor at Microdyne.


--
Never **** off an Engineer!

They don't get mad.

They don't get even.

They go for over unity! ;-)