[TenTec] Dual frequency receive

[Dr. Gerald N. Johnson]

On Mon, 2006-12-25 at 16:11 -1000, Ken Brown wrote:
> 
> 
> > do I have to switch back and forth to listen to both.
> >   
> You can switch back and forth between frequencies, to listen to both 
> (not simultaneously) without having two VFOs. You just need one VFO with 
> two (easy to switch between) memories. This is what most transceivers 
> with an A and B internal VFO have. They typically do not really have two 
> VFOs.
> 
> If you truly have two VFOs, as was common with separate matching 
> transmitters and receivers (such as the Drake 4 line, Heath SB series 
> and Collins S-line) and some older transceivers with external accessory 
> VFOs, then it is possible to have both VFOs combined into the LO port of 
> the mixer and receive two frequencies (on the same band) simultaneously.

I don't remember that the Collins, Drake, or Heathkit allowed
simultaneous reception without user mods.
> 
> I have never operated a rig that had this feature from the factory. 
> Apparently there are several rigs that have this feature without 
> modification, and some of them have a control that allows variable 
> relative levels of the two VFOs and therefore of the two received 
> frequencies.
> 
The external VFO for some Tentecs like the Corsair II has a switch to
allow simultaneous reception on two frequencies in the same band and has
a control to select the relative sensitivities.

> DE N6KB
> 
73, Jerry, K0CQ