In article ,
says...


Guy Atkins wrote:

The NRD-515 is a fine model, Pete. Congratulations on a acquiring one and
the quick fix you did!

I consider the NRD-515 the receiver equivalent of the '55 Chevy amongst
1980s-vintage radios. It's large, it's well built, and it has a sort of
no-nonsense beauty to it. Back when the NRD was popular, I went the Drake
R-7 route instead, but I always admired the NRD-515. I later owned a NRD-525
and had fun doing various mods to it, but that model just doesn't have the
"karma" of the NRD-515.

I had a '515 for a bit and it was indeed very nicely built. The thing I didn't
like about it was the audio, though I understand that that could be rectified.

dxAce
Michigan
USA



Guy

"Pete KE9OA" wrote in message
...
I understand why you feel that way about it..........I didn't realize that
it was that good of a design. I like that MW preselector control. I was
really surprised to find silver mica caps in the front end. They didn't
skimp on this one.
Of course, the big question might be "how does it compare to the Lowe
receivers?"
Very similar in operation. It appears that most of the modern receiver
designs have about the same sensitivity; the differences would be in
overload performance.

Pete

"BDK" wrote in message
...
In article ,
says...
I picked up this receiver today. Some fellow traded it even up with a
friend
of mine for an R4C. I traded a Takahashi FS-78 Flourite refractor for
it. If
the JRC unit was working properly, it would have been a good deal, but I
thought, "what the heck?"
When I put it on my test bench, it could barely hear a 60% modulated
10uV
signal...........not good.
I did download a schematic from a Dutch website and saw that the 1st
mixer
uses U310 JFETs. No big deal, right?
When I removed the shield from the mixer assembly, I discovered that
instead
of the U310s, a Siliconix E431 dual JFET is used. This is a very high
IP3
mixer, capable of +20 to +30dBm in a properly designed circuit.
I bought a batch of them several years ago from, you guessed
it....................the Rockwell-Collins surplus store.
I replaced the defective component and now the receiver is hearing
signals
all the way down to .1uV, which is typical of any of the modern day
receivers that use this topology.
I have been looking for one of these receivers for a few years; it's
ironic
that about the only way that you can get ahold of them is if they are in
need of repair. It wasn't too bad..........about an hour or so for the
repair.
Now I see why people don't want to sell these receivers. Good
quality......................even the roofing filter appears to be a 6
or
8-pole unit. This one's a keeper!

Pete




I've had mine since late 85. All of my other ones will probably go away
sooner or later, but unless my 515 dies and I can't get it fixed, it
will be here when I'm carted off...never to return...

BDK






If you run the line out to an amp, it's not bad at all. I have it hooked
to a Sony surround receiver with a "splitter", so it goes to both
channels and it's very nice. My only problem right now is that it needs
to be aligned. I should get me a new freq counter and just do it
myself..


BDK

In article Ndv7e.10351$%c1.7513@fed1read05, says...
Pete, yes these are nice radios! Congratulations!! Does your have all the IF
filters installed?? I have 2 of the 515, but only one NDH-518 external
memory unit. Did you get a memory unit with yours?? I also have the big
brother to the 515, that is the NRD-505.. Purchased it on eBay about 3
years ago! Listed it as not working with a buy It Now price of $200.00..
Grabbed it right up... After replacing the AC power fuse, radio has been
100% ever since... The 515 is just nice to operate. The Tunable RF front end
on AM radio band is just a great feature... Enjoy the radio!!





Damn, I always wanted a 505. They only made a few of them, compared to
most of the other JRC radios. I played with one at Universal about 20
years ago. I think they wanted 1200 for it at that time. I used to go
down there a lot, and saw many a nice toy I drooled over..

I can't complain though, I got an Icom R-71A for 50 bucks plus shipping.
Was dead and the owner wanted to dump it after spending a couple hundred
bucks trying to get it fixed. I had it going in a half hour, just a few
really loose screws and a amazingly bad solder joint. Now if the dope
who sold it to me hadn't put the PBT/Notch knobs in some kind of cleaner
to get the crud off and forgotten them, it would be a 8-9 out of 10. It
ate the knobs so bad they were worthless. Those knobs are just about
impossible to get..

Not like you really need them anyway..

BDK

Muffled wooly audio seemed to be a hallmark of the NRD series. I've
tried three different models and they all had narrow soft audio on the
widest AM filter. Sounded much better in SSB though.

"Guy Atkins" wrote in message
...
The NRD-515 is a fine model, Pete. Congratulations on a acquiring one and
the quick fix you did!

I consider the NRD-515 the receiver equivalent of the '55 Chevy amongst
1980s-vintage radios. It's large, it's well built, and it has a sort of
no-nonsense beauty to it. Back when the NRD was popular, I went the Drake
R-7 route instead, but I always admired the NRD-515. I later owned a
NRD-525 and had fun doing various mods to it, but that model just doesn't
have the "karma" of the NRD-515.

Guy

It a fun receiver............it reminds me of the 651S-1 that I had years
ago. I think it is that die-cast front panel.
I've had a couple of R7s over the years. Nice receiver.

Pete

"RSL" wrote in message
news:Ndv7e.10351$%c1.7513@fed1read05...
Pete, yes these are nice radios! Congratulations!! Does your have all the
IF filters installed?? I have 2 of the 515, but only one NDH-518 external
memory unit. Did you get a memory unit with yours?? I also have the big
brother to the 515, that is the NRD-505.. Purchased it on eBay about 3
years ago! Listed it as not working with a buy It Now price of $200.00..
Grabbed it right up... After replacing the AC power fuse, radio has been
100% ever since... The 515 is just nice to operate. The Tunable RF front
end on AM radio band is just a great feature... Enjoy the radio!!


This one only has the AM and SSB filters. It looks like a filter board plugs
into a gold plated edge connector on the main board. I should make up a
daughter board so I can install those extra filters.
That 505 was a super receiver. Super deal!

Pete