Wanted repair parts: JRC NRD-91 – need tuning control and push
buttons . . .

Greetings all,

I am in the process of repairing an old JRC NRD-91 shortwave receiver.

I found that the digital tuning control is bad.

It is a digital “pulser” – I think they call it 2-bit gray code with
50 pulses to the turn. (Not sure about that.)
I also need some of the buttons that are used on the front panel.

Does anyone have any of these parts? Or, has anyone been successful in
retrofitting with a part that I can find.
I am going to try and fix the tuning control. It is cracked at the
place where the leads leave the unit.

I will try to bridge the broken circuit on the control with conductive
epoxy. I will post back how well that works out. But first, I need to
obtain some conductive epoxy. :-)

Thanks all,

- Stan Shankman (K7SJB)

What you need is a simple Quadrature shaft encoder, not a gray code encoder.
A Grayhill or an Oak Grisby unit will run you about 30 to 40 dollars.
Nothing special about the one in the JRC unit. I do have an NRD-91
myself............good receiver.
There is a fellow on eBay that has the manual, along with the schematics in
PDF form for about 20 dollars with a "Buy it Now" option. I bought one from
him a few months back.

Pete

Pete
"Stan (K7SJB)" wrote in message
...
Wanted repair parts: JRC NRD-91 – need tuning control and push
buttons . . .

Greetings all,

I am in the process of repairing an old JRC NRD-91 shortwave receiver.

I found that the digital tuning control is bad.

It is a digital “pulser” – I think they call it 2-bit gray code with
50 pulses to the turn. (Not sure about that.)
I also need some of the buttons that are used on the front panel.

Does anyone have any of these parts? Or, has anyone been successful in
retrofitting with a part that I can find.
I am going to try and fix the tuning control. It is cracked at the
place where the leads leave the unit.

I will try to bridge the broken circuit on the control with conductive
epoxy. I will post back how well that works out. But first, I need to
obtain some conductive epoxy. :-)

Thanks all,

- Stan Shankman (K7SJB)

Pete,
Thanks for the reply.
Knowing the names "Grayhill" and "Oak Grisby" (recently acquired by
Electroswitch) makes it a lot easier to search eBay for replacement parts. I
will keep looking.
I do have a schematic diagram for my NRD-91, but not the parts list. Do you
have that? If so, would you please check and see what the manufacturer has
for parts info?
I am not at all opposed to retrofitting in an optical encoder, but I would
like to know how many "clicks" to the turn the original has. I may be able
to remove the lid on mind and use magnification and just count them. Of
course I need to remove the existing encoder first, so I can take reliable
physical measurements. I defiantly want to reuse the original know and I
think it would be nice to have the same number of counts per revolution (but
who know? Maybe certain modern optical encoders with more or less counts per
turn would work out to be more desirable.
So thanks again for what you told me, and I am still looking for that
conductive epoxy.
:-)-
Stan (K7SJB)


"Pete KE9OA" wrote in message
. ..
What you need is a simple Quadrature shaft encoder, not a gray code
encoder. A Grayhill or an Oak Grisby unit will run you about 30 to 40
dollars. Nothing special about the one in the JRC unit. I do have an
NRD-91 myself............good receiver.
There is a fellow on eBay that has the manual, along with the schematics
in PDF form for about 20 dollars with a "Buy it Now" option. I bought one
from him a few months back.

Pete

Pete
"Stan (K7SJB)" wrote in message
...
Wanted repair parts: JRC NRD-91 - need tuning control and push
buttons . . .

Greetings all,

I am in the process of repairing an old JRC NRD-91 shortwave receiver.

I found that the digital tuning control is bad.

It is a digital "pulser" - I think they call it 2-bit gray code with
50 pulses to the turn. (Not sure about that.)
I also need some of the buttons that are used on the front panel.

Does anyone have any of these parts? Or, has anyone been successful in
retrofitting with a part that I can find.
I am going to try and fix the tuning control. It is cracked at the
place where the leads leave the unit.

I will try to bridge the broken circuit on the control with conductive
epoxy. I will post back how well that works out. But first, I need to
obtain some conductive epoxy. :-)

Thanks all,

- Stan Shankman (K7SJB)

Hi Stan,

It appears that I have the same information that you do. A 64 pulse per
revolution unit should do the trick, but I am not sure.

Pete

"Stan Shankman" wrote in message
...
Pete,
Thanks for the reply.
Knowing the names "Grayhill" and "Oak Grisby" (recently acquired by
Electroswitch) makes it a lot easier to search eBay for replacement parts.
I will keep looking.
I do have a schematic diagram for my NRD-91, but not the parts list. Do
you have that? If so, would you please check and see what the manufacturer
has for parts info?
I am not at all opposed to retrofitting in an optical encoder, but I would
like to know how many "clicks" to the turn the original has. I may be able
to remove the lid on mind and use magnification and just count them. Of
course I need to remove the existing encoder first, so I can take reliable
physical measurements. I defiantly want to reuse the original know and I
think it would be nice to have the same number of counts per revolution
(but who know? Maybe certain modern optical encoders with more or less
counts per turn would work out to be more desirable.
So thanks again for what you told me, and I am still looking for that
conductive epoxy.
:-)- Stan (K7SJB)


"Pete KE9OA" wrote in message
. ..
What you need is a simple Quadrature shaft encoder, not a gray code
encoder. A Grayhill or an Oak Grisby unit will run you about 30 to 40
dollars. Nothing special about the one in the JRC unit. I do have an
NRD-91 myself............good receiver.
There is a fellow on eBay that has the manual, along with the schematics
in PDF form for about 20 dollars with a "Buy it Now" option. I bought one
from him a few months back.

Pete

Pete
"Stan (K7SJB)" wrote in message
...
Wanted repair parts: JRC NRD-91 - need tuning control and push
buttons . . .

Greetings all,

I am in the process of repairing an old JRC NRD-91 shortwave receiver.

I found that the digital tuning control is bad.

It is a digital "pulser" - I think they call it 2-bit gray code with
50 pulses to the turn. (Not sure about that.)
I also need some of the buttons that are used on the front panel.

Does anyone have any of these parts? Or, has anyone been successful in
retrofitting with a part that I can find.
I am going to try and fix the tuning control. It is cracked at the
place where the leads leave the unit.

I will try to bridge the broken circuit on the control with conductive
epoxy. I will post back how well that works out. But first, I need to
obtain some conductive epoxy. :-)

Thanks all,

- Stan Shankman (K7SJB)