01-12-2016, 08:49 PM
Apart from the legendary VK3HZ riglock boards I have been exploring alternate ways of locking the IC910h to a GPS 1pps source.
This week i have been testing a progrock to see if it does what it claims it can. (google progrock)
The 2 i bought do work, one however doesnt like being programmed....but it does respond to 010<enter> and becomes a 10MHz source by reset.
The other one programmed up ok and is now on 30.2MHz which is the frequency of the master oscillator in the ICOM IC910h.
So, lets see if it actually will lock to a 1pps source.
Firstly i tried a garmin gps head (black , model 35) with 1pps enabled, except it produces a one second ttl data burst from the grey wire instead of a nice clean 1pps pulse. The progrock didnt like that.
I hunted around and found a ne555 to use as a one shot to try and clean up the pulse , but struck problems with the old ne555,its not the cmos version. didnt have any. gave up.
Next was the 1pps from the Chinese GPSDO from BG7TBL. These units are really good and work well. search ebay
Mine is still running on the bench now, locking its own internal 10MHz oscillator, and the 1pps is locking the progrock pll as well.
This means you can use a progrock to lock your ICOM IC910h (or other radio with master oscillator within the progrock frequency range like a ft817) and have a 10 MHz source to lock your transverters to as well.
And the combination of the GPSDO and the progrock draws only 350 mA from a 12 volt battery supply, so its perfect for mountaintop field day use on the microwave bands, especially if you are running digital modes.
Getting the BG7TBL GPSDO to run off a 12 volt unregulated battery power source is the subject of another paper i will have to write up.
The point of the exercise is to lock both the radio and the transverters , and this seems to the the most cost effective way.
I listened to the 30.2 MHz signal on the ICOM 746pro as the progrock was locking itself to the 1 pulse per second output of the GPS , and it stepped down in frequency a few hertz at a time until it settled. The process took about half a minute from start to finish. The makers of the progrock claim its faster every time its restarted as the old value is saved.
next job is to check the Phase noise.
73 Dave vk2jds
This week i have been testing a progrock to see if it does what it claims it can. (google progrock)
The 2 i bought do work, one however doesnt like being programmed....but it does respond to 010<enter> and becomes a 10MHz source by reset.
The other one programmed up ok and is now on 30.2MHz which is the frequency of the master oscillator in the ICOM IC910h.
So, lets see if it actually will lock to a 1pps source.
Firstly i tried a garmin gps head (black , model 35) with 1pps enabled, except it produces a one second ttl data burst from the grey wire instead of a nice clean 1pps pulse. The progrock didnt like that.
I hunted around and found a ne555 to use as a one shot to try and clean up the pulse , but struck problems with the old ne555,its not the cmos version. didnt have any. gave up.
Next was the 1pps from the Chinese GPSDO from BG7TBL. These units are really good and work well. search ebay
Mine is still running on the bench now, locking its own internal 10MHz oscillator, and the 1pps is locking the progrock pll as well.
This means you can use a progrock to lock your ICOM IC910h (or other radio with master oscillator within the progrock frequency range like a ft817) and have a 10 MHz source to lock your transverters to as well.
And the combination of the GPSDO and the progrock draws only 350 mA from a 12 volt battery supply, so its perfect for mountaintop field day use on the microwave bands, especially if you are running digital modes.
Getting the BG7TBL GPSDO to run off a 12 volt unregulated battery power source is the subject of another paper i will have to write up.
The point of the exercise is to lock both the radio and the transverters , and this seems to the the most cost effective way.
I listened to the 30.2 MHz signal on the ICOM 746pro as the progrock was locking itself to the 1 pulse per second output of the GPS , and it stepped down in frequency a few hertz at a time until it settled. The process took about half a minute from start to finish. The makers of the progrock claim its faster every time its restarted as the old value is saved.
next job is to check the Phase noise.
73 Dave vk2jds