David wrote:

I think you answered your own questions, several times over.

So, this still means you think everyone should go out
and buy an old tube radio, even if it's not a R-390?

FYI, a well maintained aligned R390A in a stable environment can be
tuned within 300 Hz of a target frequency and will drift less than
half that figure over 24 hours.

Sorry. Not good enough...I used to get anal cuz my 830's
internal VFO drifted 40 cycles with A/C cycling off and on..
Even thats enough to require retuning of a SSB signal.
Thats why I went to the VFO-230 on the 830, which drifts nada..
My 706 will tune within 1 hz of a target frequency as far
as readout...If you count slewing error thoughout the HF
spectrum, the max error might be hummmm, 1-20 cycles depending
on the freq being used...Being I calibrate the radio at 10mhz,
and say I'm on 40 meters, the error will be under 5 cycles.
And I don't even have the hi-stab xtal...It could be
even better, if I wanted to spend a lil more $$$.
Within 300 hz of a target freq? Man, that's pitiful
for the year 2005...
Drift? If the room temp is stable, the icom has no real
drift. Not enough to ever require retuning SSB anyway.
You'll be a long ways off from me, if you drift 150 hz
in a day. Same applies to the kenwood using the external
VFO.

You may have dynamic range, but your readout and
stability are fairly lame to my standards..



There ain't a $10 transistor made with the dynamic range of a tube
designed for small signal RF amplification.

Doesn't really matter if dynamic range is not a really much
of an issue to begin with...MK

"... Car radios can often be quite good as far as reception...."

This again. I'm not disputing you. In fact, I have yet to encounter the
home hi-fi stereo receiver that approaches a car radio in terms of
AM-MW performance. I can attest to the remarkable ability of a run of
the mill Delco car radio to haul in AM stations from miles away.

There was a page at the C. Crane site commenting on this.
brief delay while I search my files. SFX: the song played near the end
of Jeopardy while the contestants think of the answer to the final
question.

Ah, here we go:


Subject: AM Car Radios For DX?
Newsgroups: rec.radio.shortwave
Date: 2003-02-03 14:46:59 PST

Here's that website at C. Crane:
http://www.ccrane.com/news/archives/...ws10.28.02.htm


Never throw anything away. Yeah, but, attempting to open that site, I
find that the URL no longer works. One is referred to

http://www.ccrane.com/news/news-archives.aspx
and from there to

http://www.ccrane.com/news/car-radio....10.28.02.aspx
and
http://www.ccrane.com/news/car-radio....11.11.02.aspx

These pages deal largely with poor reception and noise suppression.

I agree with everything you say here.

I remember the series of modules for the High erformance HF Receiver
from the Amateur' Handbook and the discussion on the mixer as the
first active stage.

Still, to get R390-like performance (quietness, more than anything
else) a fairly esoteric receiver is necessary.

On 23 Mar 2005 18:21:13 GMT, (Michael Black)
wrote: