Hey guys, Happy New Year! Looking for ideas to cleanly phase lock a MAXTRAC. I have the boards, I have an idea on how I want to do it. Just would like input from those who already have done it. I looked online for some info but found nothing. I can break the ref osc tune line and take that signal out. I can pick off the 14.4 mhz and bring that out, but I want to do it cleanly, not a hatchet job. Anyone have pics? 73, Ron, N6GKJ Sent from Yahoo! Mail on Android
I would be VERY interested on what you come up with. This has been on my list of projects but aside from the RTCMs I don't have a source for the rest of the gear. What are you planning on using to convert the 10mhz ref signal to 14.4? I figured I'd be stuck buying Mastr III's or MTR2000's k0jsc On Wed, Jan 2, 2013 at 10:22 AM, Ron Simpson <n6gkj.cm98@yahoo.com> wrote:
Hey guys, Happy New Year!
Looking for ideas to cleanly phase lock a MAXTRAC. I have the boards, I have an idea on how I want to do it. Just would like input from those who already have done it. I looked online for some info but found nothing.
I can break the ref osc tune line and take that signal out. I can pick off the 14.4 mhz and bring that out, but I want to do it cleanly, not a hatchet job.
Anyone have pics?
73, Ron, N6GKJ
Sent from Yahoo! Mail on Android
_______________________________________________ App_rpt-users mailing list App_rpt-users@ohnosec.org http://ohnosec.org/cgi-bin/mailman/listinfo/app_rpt-users
I'm also interested in locking a transmitter frequency to stable reference. The ICOM FR-6000 repeater which I use has a TI LMX2352 PLL which relies on a 15.3 MHz Crystal Resonator, CR-826 type. It appears that I might be able to replace the crystal with a reflock board (Link below), with the reflock generating the 15.3 MHz. http://www.qsl.net/ct1dmk/reflock.html Here is an example of a ham reflock'ing a yaesu 817 all-mode radio to a 10 MHz reference input http://www.vk3hz.net/riglock/FT817_External_Reference.pdf The 10 MHz reference signal can be from a Rubidium Oscillator or from GPS Disciplined Oscillator, both of which are available from eBay. The Trimble Thunderbolt is a common GPSDO. Some good general info is on John's web site: http://www.ke5fx.com/tbolt.htm 73, Randy - VE3RWN / W3RWN On Wed, Jan 2, 2013 at 12:22 PM, Ron Simpson <n6gkj.cm98@yahoo.com> wrote:
Hey guys, Happy New Year!
Looking for ideas to cleanly phase lock a MAXTRAC. I have the boards, I have an idea on how I want to do it. Just would like input from those who already have done it. I looked online for some info but found nothing.
I can break the ref osc tune line and take that signal out. I can pick off the 14.4 mhz and bring that out, but I want to do it cleanly, not a hatchet job.
Anyone have pics?
73, Ron, N6GKJ
Sent from Yahoo! Mail on Android
_______________________________________________ App_rpt-users mailing list App_rpt-users@ohnosec.org http://ohnosec.org/cgi-bin/mailman/listinfo/app_rpt-users
One thing you should be aware of is that replacing a crystal with a reflock, or similar, will increase phase noise and spurious outputs of the attached PLL. In FM this will probably show up as reduced adjacent channel rejection. If you are not in a dense-signal environment, this may not be an issue. In any case, you need to adjust the level of the replacement signal into the PLL carefully for minimum crud generation. Watching the output of the PLL on a spectrum analyzer would be a good idea. 73 Ken From: app_rpt-users-bounces@ohnosec.org [mailto:app_rpt-users-bounces@ohnosec.org] On Behalf Of Randy Neals Sent: Friday, January 04, 2013 7:30 PM To: Ron Simpson Cc: app_rpt-users@ohnosec.org Subject: Re: [App_rpt-users] GPS Locked MACTRAC I'm also interested in locking a transmitter frequency to stable reference. The ICOM FR-6000 repeater which I use has a TI LMX2352 PLL which relies on a 15.3 MHz Crystal Resonator, CR-826 type. It appears that I might be able to replace the crystal with a reflock board (Link below), with the reflock generating the 15.3 MHz. http://www.qsl.net/ct1dmk/reflock.html Here is an example of a ham reflock'ing a yaesu 817 all-mode radio to a 10 MHz reference input http://www.vk3hz.net/riglock/FT817_External_Reference.pdf The 10 MHz reference signal can be from a Rubidium Oscillator or from GPS Disciplined Oscillator, both of which are available from eBay. The Trimble Thunderbolt is a common GPSDO. Some good general info is on John's web site: http://www.ke5fx.com/tbolt.htm 73, Randy - VE3RWN / W3RWN On Wed, Jan 2, 2013 at 12:22 PM, Ron Simpson <n6gkj.cm98@yahoo.com> wrote: Hey guys, Happy New Year! Looking for ideas to cleanly phase lock a MAXTRAC. I have the boards, I have an idea on how I want to do it. Just would like input from those who already have done it. I looked online for some info but found nothing. I can break the ref osc tune line and take that signal out. I can pick off the 14.4 mhz and bring that out, but I want to do it cleanly, not a hatchet job. Anyone have pics? 73, Ron, N6GKJ Sent from Yahoo! Mail on Android _______________________________________________ App_rpt-users mailing list App_rpt-users@ohnosec.org http://ohnosec.org/cgi-bin/mailman/listinfo/app_rpt-users
The reflock does not have it's own oscillator, it sniffs the tcxo as an input and has a dc output to control the comp line or such of the tcxo osc. It has an additional input for the ref osc like 10mhz gps etc... The boards function is to have 2 pll oscillators based on the 2 frequencies of input and scaled, to mathematically lock to each other...and keep it mathematically locked. In general it should at most introduce a little jitter but should be no phase noise that I am aware of.. It does not replace your tcxo it just watches it and controls it.. Doug KD8B On 1/4/2013 8:16 PM, Ken wrote:
One thing you should be aware of is that replacing a crystal with a reflock, or similar, will increase phase noise and spurious outputs of the attached PLL. In FM this will probably show up as reduced adjacent channel rejection. If you are not in a dense-signal environment, this may not be an issue. In any case, you need to adjust the level of the replacement signal into the PLL carefully for minimum crud generation. Watching the output of the PLL on a spectrum analyzer would be a good idea.
73
Ken
*From:*app_rpt-users-bounces@ohnosec.org [mailto:app_rpt-users-bounces@ohnosec.org] *On Behalf Of *Randy Neals *Sent:* Friday, January 04, 2013 7:30 PM *To:* Ron Simpson *Cc:* app_rpt-users@ohnosec.org *Subject:* Re: [App_rpt-users] GPS Locked MACTRAC
I'm also interested in locking a transmitter frequency to stable reference. The ICOM FR-6000 repeater which I use has a TI LMX2352 PLL which relies on a 15.3 MHz Crystal Resonator, CR-826 type.
It appears that I might be able to replace the crystal with a reflock board (Link below), with the reflock generating the 15.3 MHz. http://www.qsl.net/ct1dmk/reflock.html
Here is an example of a ham reflock'ing a yaesu 817 all-mode radio to a 10 MHz reference input http://www.vk3hz.net/riglock/FT817_External_Reference.pdf
The 10 MHz reference signal can be from a Rubidium Oscillator or from GPS Disciplined Oscillator, both of which are available from eBay. The Trimble Thunderbolt is a common GPSDO. Some good general info is on John's web site: http://www.ke5fx.com/tbolt.htm
73,
Randy - VE3RWN / W3RWN
On Wed, Jan 2, 2013 at 12:22 PM, Ron Simpson <n6gkj.cm98@yahoo.com <mailto:n6gkj.cm98@yahoo.com>> wrote:
Hey guys, Happy New Year!
Looking for ideas to cleanly phase lock a MAXTRAC. I have the boards, I have an idea on how I want to do it. Just would like input from those who already have done it. I looked online for some info but found nothing.
I can break the ref osc tune line and take that signal out. I can pick off the 14.4 mhz and bring that out, but I want to do it cleanly, not a hatchet job.
Anyone have pics?
73, Ron, N6GKJ
Sent from Yahoo! Mail on Android
_______________________________________________ App_rpt-users mailing list App_rpt-users@ohnosec.org <mailto:App_rpt-users@ohnosec.org> http://ohnosec.org/cgi-bin/mailman/listinfo/app_rpt-users
_______________________________________________ App_rpt-users mailing list App_rpt-users@ohnosec.org http://ohnosec.org/cgi-bin/mailman/listinfo/app_rpt-users
participants (5)
-
Doug Bade -
Jeff Carrier -
Ken -
Randy Neals -
Ron Simpson