Re: [time-nuts] Thunderbolt no usable sats.
Thanks for all the information, this is an great group. Does anyone have the shematic on the box? BR. Thomas. 2011/6/12 Ed Palmer ed_pal...@sasktel.net: Is there more than one hardware version of the T'bolt? Mine has U18 (right behind the RS-232 connector) as an Intersil ICL232IBE. This is a dual RS-232 transceiver that includes a doubler and inverter to generate plus and minus 9 to 10 volts from the +5 input. It appears to have the required capacitors on the bottom of the board. The open circuit RS-232 voltages on mine are just under 10 volts which seems a little low for a 12 volt source. I didn't try to run mine without -12, but the presence of that chip and messages on this list made me think that the -12 was only used for the DAC. Ed WarrenS wrote: I've run test of the effect of the Neg supply on a Tbolt's operation and the effect on it's noise. (It would seem I'm one of few nuts that actually test things) The Neg supply effects the RS232 neg swing and the neg output of the DAC. As long as the Dac out (OSC EFC input) is than a couple of volts above the neg supply (or the EFC is positive) all worked fine at any Neg supply down to -3 volts. This is because most RS232 receivers don't need their input to swing negative. Your -7 volts statement agrees well with my test. You can go even lower on the neg supply with no ill effects IF you do not need the DAC output to go all the way to neg -5Volts. ws PS I did not test for the effects with a Neg supply less than -3 volts, It may of been able to go even lower, I just wanted to insure it was reliable with -5 volts for my application. ** [time-nuts] Thunderbolt no usable sats. Arthur Dent golgarfrincham at yahoo.com It may or may not be used for tuning voltage but what I said is 100% correct. The Andrew/Grayson units these T-Bolts were used in provided -7 VDC for this negative supply and the same T-Bolts work properly on -12 VDC. If this voltage is missing, the com port will not work. +++ Please read what I actually said. Do you disagree that these units will not run on -7 VDC or that the com port will not work if the negative supply is missing? -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. -- Please avoid sending me Word or PowerPoint attachments. See http://www.gnu.org/philosophy/no-word-attachments.html ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Thunderbolt no usable sats.
I bougth an Thunderbolt off E-bay some time ago, to use as reference for my spectrum analyzer and signal generators. I had it connected up with a couple of power supplies and it worked as it should. Today I put together an voltage inverter to get the -12V to the GPS in order to use it with an single 12V power supply. The -12 requires 10 ma according to the manual but in reality probably draws about 2 ma so loading shouldn't be a problem. You didn't mention the 5 volt supply at all. The +5 VDC should be able to supply at least 400 ma and the +12 VDC 750 ma. Ripple and noise should be around 15 MV max for the +5 VDC and 20 MV for the +/-12 VDC. The -12 VDC is used for the RS-232 so if that was giving you the problem you wouldn't see anything on your com port (note it will work at -7 VDC or so) and if the +5 VDC was off you wouldn't see anything on Lady Heather. The +12 VDC is for the oven. If the unit was working before on the other supply, go back to that supply and make sure it still works to see if it is your new supply setup or maybe you accidently fried something. If it works on the old supply, connect the new supply and recheck all connections and voltages both with a meter and a scope (or your spectrum analyser) to see if there is anything unusual. -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Thunderbolt no usable sats.
the -12 VDC is also used by the OCXO as tuning voltage! Bert Kehren In a message dated 6/12/2011 6:05:01 A.M. Eastern Daylight Time, golgarfrinc...@yahoo.com writes: I bougth an Thunderbolt off E-bay some time ago, to use as reference for my spectrum analyzer and signal generators. I had it connected up with a couple of power supplies and it worked as it should. Today I put together an voltage inverter to get the -12V to the GPS in order to use it with an single 12V power supply. The -12 requires 10 ma according to the manual but in reality probably draws about 2 ma so loading shouldn't be a problem. You didn't mention the 5 volt supply at all. The +5 VDC should be able to supply at least 400 ma and the +12 VDC 750 ma. Ripple and noise should be around 15 MV max for the +5 VDC and 20 MV for the +/-12 VDC. The -12 VDC is used for the RS-232 so if that was giving you the problem you wouldn't see anything on your com port (note it will work at -7 VDC or so) and if the +5 VDC was off you wouldn't see anything on Lady Heather. The +12 VDC is for the oven. If the unit was working before on the other supply, go back to that supply and make sure it still works to see if it is your new supply setup or maybe you accidently fried something. If it works on the old supply, connect the new supply and recheck all connections and voltages both with a meter and a scope (or your spectrum analyser) to see if there is anything unusual. -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Thunderbolt no usable sats.
Arthur Dent-The -12 VDC is used for the RS-232 so if that was giving you the problem you wouldn't see anything on your com port (note it will work at -7 VDC or so)... the -12 VDC is also used by the OCXO as tuning voltage! Bert Kehren It may or may not be used for tuning voltage but what I said is 100% correct. The Andrew/Grayson units these T-Bolts were used in provided -7 VDC for this negative supply and the same T-Bolts work properly on -12 VDC. If this voltage is missing, the com port will not work. -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Thunderbolt no usable sats.
The -12V is almost certainly used for deriving the tuning voltage. The unit can generate a tuning voltage of -5V to +5V. To do this it needs a negative supply... and there does not seem to be an on board bias generator for generating the negative DAC supply. Becuase of this, for best tbolt performance, you probably should not use a schlocky -12V supply. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Thunderbolt no usable sats.
Thank you Mark. It is not almost certain it is a fact. Bert -Original Message- From: Mark Sims hol...@hotmail.com To: time-nuts@febo.com Sent: Sun, Jun 12, 2011 10:04 am Subject: [time-nuts] Thunderbolt no usable sats. The -12V is almost certainly used for deriving the tuning voltage. The unit can generate a tuning voltage of -5V to +5V. To do this it needs a negative supply... and there does not seem to be an on board bias generator for generating the negative DAC supply. Becuase of this, for best tbolt performance, you probably should not use a schlocky -12V supply. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Thunderbolt no usable sats.
It may or may not be used for tuning voltage but what I said is 100% correct. The Andrew/Grayson units these T-Bolts were used in provided -7 VDC for this negative supply and the same T-Bolts work properly on -12 VDC. If this voltage is missing, the com port will not work. +++ Please read what I actually said. Do you disagree that these units will not run on -7 VDC or that the com port will not work if the negative supply is missing? -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Thunderbolt no usable sats.
I've run test of the effect of the Neg supply on a Tbolt's operation and the effect on it's noise. (It would seem I'm one of few nuts that actually test things) The Neg supply effects the RS232 neg swing and the neg output of the DAC. As long as the Dac out (OSC EFC input) is than a couple of volts above the neg supply (or the EFC is positive) all worked fine at any Neg supply down to -3 volts. This is because most RS232 receivers don't need their input to swing negative. Your -7 volts statement agrees well with my test. You can go even lower on the neg supply with no ill effects IF you do not need the DAC output to go all the way to neg -5Volts. ws PS I did not test for the effects with a Neg supply less than -3 volts, It may of been able to go even lower, I just wanted to insure it was reliable with -5 volts for my application. ** [time-nuts] Thunderbolt no usable sats. Arthur Dent golgarfrincham at yahoo.com It may or may not be used for tuning voltage but what I said is 100% correct. The Andrew/Grayson units these T-Bolts were used in provided -7 VDC for this negative supply and the same T-Bolts work properly on -12 VDC. If this voltage is missing, the com port will not work. +++ Please read what I actually said. Do you disagree that these units will not run on -7 VDC or that the com port will not work if the negative supply is missing? -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Thunderbolt no usable sats.
Is there more than one hardware version of the T'bolt? Mine has U18 (right behind the RS-232 connector) as an Intersil ICL232IBE. This is a dual RS-232 transceiver that includes a doubler and inverter to generate plus and minus 9 to 10 volts from the +5 input. It appears to have the required capacitors on the bottom of the board. The open circuit RS-232 voltages on mine are just under 10 volts which seems a little low for a 12 volt source. I didn't try to run mine without -12, but the presence of that chip and messages on this list made me think that the -12 was only used for the DAC. Ed WarrenS wrote: I've run test of the effect of the Neg supply on a Tbolt's operation and the effect on it's noise. (It would seem I'm one of few nuts that actually test things) The Neg supply effects the RS232 neg swing and the neg output of the DAC. As long as the Dac out (OSC EFC input) is than a couple of volts above the neg supply (or the EFC is positive) all worked fine at any Neg supply down to -3 volts. This is because most RS232 receivers don't need their input to swing negative. Your -7 volts statement agrees well with my test. You can go even lower on the neg supply with no ill effects IF you do not need the DAC output to go all the way to neg -5Volts. ws PS I did not test for the effects with a Neg supply less than -3 volts, It may of been able to go even lower, I just wanted to insure it was reliable with -5 volts for my application. ** [time-nuts] Thunderbolt no usable sats. Arthur Dent golgarfrincham at yahoo.com It may or may not be used for tuning voltage but what I said is 100% correct. The Andrew/Grayson units these T-Bolts were used in provided -7 VDC for this negative supply and the same T-Bolts work properly on -12 VDC. If this voltage is missing, the com port will not work. +++ Please read what I actually said. Do you disagree that these units will not run on -7 VDC or that the com port will not work if the negative supply is missing? -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Thunderbolt no usable sats.
WarrenS-.As long as the Dac out (OSC EFC input) is than a couple of volts above the neg supply (or the EFC is positive) all worked fine at any Neg supply down to -3 volts. This is because most RS232 receivers don't need their input to swing negative. Your -7 volts statement agrees well with my test. You can go even lower on the neg supply with no ill effects IF you do not need the DAC output to go all the way to neg -5Volts. A previous thread concerning the Fluke.l monitor (Tbolt LCD Monitor - No DAC reading) also supports this. A few T-Bolt/monitor owners had problems with the DAC voltage displaying 0. when it was actually slightly negative, around -0.1000 VDC. I've had about 50 T-Bolts and although I never recorded the DAC voltage displayed with Lady Heather, I believe they were all positive and less than 1 volt. The fact that only a few T-Bolt/monitor owners report this problem of displaying negative DAC voltages may support my guess that the DAC voltage needed for EFC is more likely to be positive than negative. If this is the case then perhaps you might be able to go less than -3 (or technically greater than-toward zero volts) on many T-Bolt units but I wouldn't recommend it. -Arthur ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
[time-nuts] Thunderbolt no usable sats.
I bougth an Thunderbolt off E-bay some time ago, to use as reference for my spectrum analyzer and signal generators. I had it connected up with a couple of power supplies and it worked as it should. Today I put together an voltage inverter to get the -12V to the GPS in order to use it with an single 12V power supply. When re-starting the GPS, it did an servey but did not find any usable satelites, I did think that it just needed some time, and left it on for a couple of hours. It still show no usable sats. When monitoring the GPS with Lady Heather the clock show an time, but it states no usable sats and none are visible in the map. The GPS antenna is in the attic and have approx 25dB gain (with cable loss). Is there any known issues with this? I did look through the archives but found nothing. Is the -12V used for more than the RS-232? if not, would it be possible to replace it with an other type that don't ned -12V? BR Thomas. -- Please avoid sending me Word or PowerPoint attachments. See http://www.gnu.org/philosophy/no-word-attachments.html ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
Re: [time-nuts] Thunderbolt no usable sats.
Hello Thomas, The first question is did you measure the minus 12 output of your inverter to make sure it was not being loaded down too far when powering the Thunderbolt ? If it was working on the original minus 12 volt supply properly, then it would seem that there is a problem with your inverter. I would consider hooking up the original negative supply and measuring the current consumption to see if it is too high for the inverter circuit. BillWB6BNQ Thomas S. Knutsen wrote: I bougth an Thunderbolt off E-bay some time ago, to use as reference for my spectrum analyzer and signal generators. I had it connected up with a couple of power supplies and it worked as it should. Today I put together an voltage inverter to get the -12V to the GPS in order to use it with an single 12V power supply. When re-starting the GPS, it did an servey but did not find any usable satelites, I did think that it just needed some time, and left it on for a couple of hours. It still show no usable sats. When monitoring the GPS with Lady Heather the clock show an time, but it states no usable sats and none are visible in the map. The GPS antenna is in the attic and have approx 25dB gain (with cable loss). Is there any known issues with this? I did look through the archives but found nothing. Is the -12V used for more than the RS-232? if not, would it be possible to replace it with an other type that don't ned -12V? BR Thomas. -- Please avoid sending me Word or PowerPoint attachments. See http://www.gnu.org/philosophy/no-word-attachments.html ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. ___ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
