Call a crystal manufacturer and tell them what radio you have and what
frequency you want to use. They have the specs for just about everything.

Dave WD9BDZ

Tim Wescott wrote:
"Eddie Haskel" wrote in message
. com...

I thought the regency's were... operating frequency minus 10.7Mhz divided
by ***3*** not 9! that would put the crystal around 45.0Mhz. The crystal

IS

a 3rd overtone..but should be in the 45 Mhz area....Eddie.
"Tim Wescott" wrote in message
...

"KU2S" wrote in message
...

Hi folks.. Have a Regency HR-2A that I want to re-crystal for packet
use, but don't have the manual, and therefore do not have the formula
for calculating the frequency of the receive and transmit crystals for
desired frequency of operation. Could anyone out there help with this
info? Hamfest coming up this weekend and I'd like to shop for
crystals. Also, is there a .PDF of the manual available anywhere?
I've searched the web and there are plenty of folks who'll sell me a
photocopy of the manual for anywhere from $15.00 to $25.00, but to be
honest, that would exceed the value of the radio... Any help would be
greatly appreciated...

Thanks much, and 73!


Raymond Sirois KU2S
SysOp: The Lost Chord BBS
607-733-5745
telnet://thelostchord.dns2go.com:6000

I know nothing about that rig, but in general you can check if any of

the

existing crystals are stamped with their actual operating frequency, and
figure it out.

I assume it's a two meter rig. Normally the transmit crystals will be

some

integer fraction of the transmit frequency, like 6 or 8 or 9, so a

144.0MHz

transmit frequency would have a crystal frequency of 24MHz (6x), 18MHz

(8x)

or 16MHz (9x). Receive will be receive frequency +/- the IF frequency
(almost certainly 10.7MHz), divided by some fraction, so 144MHz would be
something like 19.338MHz ( (144 + 10.7)/8 ) or 16.663MHz ( (144 -

10.7)/8 ).

This sounds daunting, but if you can noodle around with a calculator

without

loosing track (or use a spreadsheet!), you can figure it out.




As I said, I know nothing of Regencies in particular, just that the usual
circuit is an oscillator followed by a multiplier chain. Sounds like maybe
you know the formula for this guy to use for his radio?