[R-390] R-390A (digital readout)

[chuck.rippel at cox.net]

Link corrected, below.  There is no "V" at the end one Steve's note.

Thanks for the info, Steve !

Chuck

On Wed, Mar 14, 2012 at 1:49 PM, Steve Toth wrote:

  For reference, here's the unit that is designed to work with the R390A 
- same company.
http://electronicspecialtyproducts.com/dd103.html

-- Steve, K7PZN   <http://electronicspecialtyproducts.com/dd103.htmlv>

Solution f or America: "We don't need to tax millionaires more, we need 
more millionaires to tax" 
<http://electronicspecialtyproducts.com/dd103.htmlv>

--- On Wed, 3/14/12, chuck.rippel at cox.net <chuck.rippel at cox.net> wrote:

From: chuck.rippel at cox.net <chuck.rippel at cox.net>
Subject: Re: [R-390] R-390A (digital readout)
To: r-390 at mailman.qth.net
Date: Wednesday, March 14, 2012, 10:27 AM

Interesting subject...

If the PTO end points are set up correctly so the mixing scheme and
tracking pre-selector matches the cam profiles, calibrated to the
nearest 100kc, the mechanical counter is very accurate.  I've seem some
accurate to < 100 cycles.
Frequency errors usualy mainfest themselves across band to band changes.
That is, if a receiver is calibrated to 8.2 mhz and you rotate the MC
control up to the next band, most receivers will not "land" on 9.2 mhz.
They will have to be re-calibrated.

The crystals in the oscillator drift a bit over time.  Remember also,
most are hetrodyned twice, some 3 times where the fundamental error may
be multiplied.  One could put a counter on the output but still not
capture the error caused by the crystals in the 1st oscillator.

While its not made for the R390A, perhaps something like this,
programmed to  accommodate the mixing scheme of the R390A might be very
helpful to some.

 
http://www.ebay.com/itm/190579917545?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649 
<http://www.ebay.com/itm/190579917545?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649 >
< 
http://www.ebay.com/itm/190579917545?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649 
<http://www.ebay.com/itm/190579917545?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1438.l2649> 
>

Chuck Rippel
> but how to dance in the rain"