[R-390] [Glowbugs] R-390 IF output jack freq.?

[Roy Morgan]

On Jan 28, 2014, at 4:47 PM, Dave Hooker <davehooker1951 at gmail.com> wrote:

> Hi,
> does anyone on the list remember off hand the IF output (jack) frequency on the R390?

Yes, both the R-390/URR and the R-390A have an IF of 455 kc.

A second matter is the level.  If you are feeding an SSB adapter, you need to both not overdrive the adapter, or provide too little signal.  The R-390 IF output level may be on the order of a volt or two or more.  The CV-591 SSB adapters are meant to accept this level as I understand it.

Any SSB adapter meant to get its signal through a 10 pF cap from the last IF stage may be “expecting” way less voltage.  If this is what you have, a simple two-resistor attenuator, or even a low-value volume control or pot will work fine.  You may be able to measure the IF output voltage with your DMM or VTVM.

Roy

Roy Morgan
RoyMorgan at alum.mit.edu
K1LKY Since 1958