On Sat, 04 Feb 2006 19:12:18 -0800, running dogg wrote:



I know that there are several plans on the internet for building a radio
controlled clock. These involve building a fixed frequency rx and then
hooking it up to a clock. How feasible would it be to hook the same
circuit up to an amp and speaker instead of a clock?

I haven't looked at any of these circuits, but I'd expect it to be
quire easy to connect and audio amplifier and speaker to the output of
the detector.

I suspect that the
clock radios listen in on 60khz, but it should be simple to insert a
crystal or change it to get 10Mhz. Also, you could build a radio with
three frequencies-5Mhz, 10Mhz, and 15Mhz in order to take advantage of
day vs night propagation.

Converting a 60 KHz receiver to 10 MHz is likely impossible -
construction techniques and tuned circuits will be quite different -
you can almost use audio techniques and iron-core coils at 60 KHz, but
are well into RF territory at 10 MHz, and will likely have to use
air-core coils in the tuned circuits.


--
Peter Bennett, VE7CEI
peterbb4 (at) interchange.ubc.ca
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Hello Peter,


Converting a 60 KHz receiver to 10 MHz is likely impossible -
construction techniques and tuned circuits will be quite different -
you can almost use audio techniques and iron-core coils at 60 KHz, but
are well into RF territory at 10 MHz, and will likely have to use
air-core coils in the tuned circuits.


Not just that. The transmitted code is also different.

Regards, Joerg

http://www.analogconsultants.com

"Peter Bennett" wrote in message

are well into RF territory at 10 MHz, and will likely have to use
air-core coils in the tuned circuits.

Huh? Yes, he is well into RF and construction techniques will be different.
But while there are advantages to air-coil cores, their use in recievers
went out with hollow state detectors. Even in transmitters they tend to be
only used in the KW neighborhood anymore. I can't imagine that even in the
wilds of BC people are winding air coils and building on heavy steel
chassis.

...

"Joerg" wrote in message
news:TwmFf.27179

Not just that. The transmitted code is also different.

He wants to listen, and at least at 10 MHz there's something to listen TO.
The 60Khz signal is pretty strange.

...

xpyttl wrote:

"Joerg" wrote in message
news:TwmFf.27179

Not just that. The transmitted code is also different.

He wants to listen, and at least at 10 MHz there's something to listen TO.
The 60Khz signal is pretty strange.

..


No, its not. It was never intended to be listened to. It has a 1 BPS
data rate encoded time signal that has always been used to carry time
code.

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

In Europe,namely,England,they have the ten notches.
cuhulin

In other words,,, he wants to experiment? Nothing wrong with that!
cuhulin

"xpyttl" wrote in message
...
Huh? Yes, he is well into RF and construction techniques will be different.
But while there are advantages to air-coil cores, their use in recievers
went out with hollow state detectors.

I think that Coilcraft, API-Delavan, Pulse, etc. would be surprised to hear
them. Although I'd grant you that you don't typically find many air coils in
mass-market consumer electronics anymore, they're still used all over the
place in industrial and military design... where I work we buy tens of
thousands of the things every year for radio receivers!

Plenty of articles appearing in QEX and on-line also use air-core coils, since
it's a pretty fast and you can, of course, get whatever value you want with no
"minimum purchase" quantities.

---Joel Kolstad

What is the difference between air core coils and other kinds of coils?
Any advantages to using air core coils?
cuhulin

xpyttl wrote:


Not just that. The transmitted code is also different.

He wants to listen, and at least at 10 MHz there's something to listen TO.
The 60Khz signal is pretty strange.


Tobin wrote "... easier to decode". So I guess he is after decoding and
not so much after listening.

Regards, Joerg

http://www.analogconsultants.com