In article ,
Bill M wrote:

Samantha wrote:


ALSO 'someone' (lol) told me that the Grand was a rip off of another
design that was built for the TS-520 and the TS-820.. Anyone know of any
displays that were built for these radios back then?

I am not sure what radio that it actually hooks up to. I will have to
hope some of the old timers out there remember this Jewel and can come
up with some answers. I am also wondering if It could me modified to
fit other radios since it just seems to need 2-3v sine wave to make the
Freq Counter / Digital display to work...


Thanks again!!

S.

Labelling things as a rip-off is somewhat subjective. There's 'x'
number of ways to measure a frequency and if one circuit resembles
another then any similarities shouldn't be a surprise. Jeez, how many
different models of AA5 radios are there out there all using the same
basic topology?

As I suggested in the previous post I gather that the unit was a
one-size-fits-all type of display that could work with many different
radios. That would be the rationale for the three inputs.

-Bill

Well, Just a follow up.. I dropped the 820 Idea and ran with the 520S
and looked at a online manual for the radio, It seems that kenwood made
a DG-5 that connected directly to three RCA jacks and a power jack in
the back of the radio.

Looking at the DG-5 Manual, it explains,

--------------

The TS-520S operating frequency is made up as:

oprfreq = HET-(VFO+CAR)

In the The DG-5 where two counter circuits are connected in series, the
heterodyne signal is fed to the lower counter. This lower counter
subtracts 10MHZ from the heterodyne frequency in a digital way
(HET-10MHz). The subtracted frequency presets the upper counter. The
other signal fed to the upper counter is composed in the manner that the
carrier frequency is mixed with the 10MHZ reference frequency and the
resultant is further mixed with the VFO frequency. [(10MHz-CAR) - VFO].
The signal is added to the one preset by the lower counter, that is:

[(10MHz-CAR) - VFO] + (HET - 10 MHz) = HET - (VFO + CAR)

As explained above you will find that the GD-5 should display the
correct TS-520S Operating frequency. The reason of using such a
complicated construction is that if the DG-5 is the same as the TS-520S
in the construction, this can produce a signal of the same frequency as
the receive frequency. The signal interferes as spurious with the
operation of the TS-520S.

-----------------


So just giving the (H) Jack an input would yield (operating freq = (Het
- [VFO (0) + CAR (also 0)]

The power plug also is keyed identically, and plugs directly into the
radio. The manual explains that you can use this connection (13.8VDC
..9A) or use an independent power supply.

I guess the only question I have left, Is.. How did KK7US get the GD-6K
to work with a TS-820???

Looking at the manual, I saw a connector for an external VFO... but I
don't think that is where it was hooked up to.


Idea's anyone???


Thanks!!!


S.