Re: [time-nuts] strange behavior of 53230A or is the light on, but nobody in?
I have asked Agilent if stock versions of the 53230A and 53132A switched the internal oscillator out of circuit with an Ext Ref signal applied. I thought Agilent's engineer was intentionally vague but said the oscillators were indeed switched out of circuit on the counter with Ext Ref signal applied. These questions were related to several 53132A's I have seen configured with a small board back near the Ext Ref input (OPT H01 I think) that appeared to Switch the internal reference out of circuit. Agilent would not share information on the option. My question to Agilent is why sell an option and be unwilling to say what it does or how your stock unit functions? Thomas Knox From: t...@leapsecond.com Date: Mon, 17 Feb 2014 09:38:28 -1000 To: time-nuts@febo.com Subject: Re: [time-nuts] strange behavior of 53230A or is the light on, but nobody in? Bob, I'm wondering if you (or any else) has measured the PLL performance of the 53230-series? I agree it will clean up the crud but this assumes the ext ref is dirtier than the internal osc. What I found instead was that if you use a good external ref the PLL actually makes it worse. This was very disappointing. The XO version of the counter performed worse than the OCXO version even with a maser as the ext reference. Did your reading of the schematic show a way to directly use the ext ref, bypassing the noisy PLL? The other thing I found was that the ref out signal was a very polluted copy of the ref in. /tvb (i5s) On Feb 17, 2014, at 7:04 AM, Bob Camp li...@rtty.us wrote: Hi If you dig into the schematics (when they supplied them … ): The external reference goes into a phase detector. It’s one of those digital ones that can lock up to many inputs. You could feed 3. MHz in as a standard input as well as 0.5, 1, 2.5, 5, and 10 MHz. The internal oscillator (or an internal oscillator) is phase locked to the external input through a fairly narrow analog loop. The idea is to clean up the crud on the standard line. With no external reference, the PLL drops out and you go back to what ever the local reference is. Yes there’s a little more to it than that and no the circuit is not exactly the same on every counter HP ever made. Bob On Feb 17, 2014, at 7:55 AM, wb6bnq wb6...@cox.net wrote: Hi Mike, The most likely answer is when you select external time base for an input, it disables the connection for the internal oscillator. The external input signal is probably also routed straight to the reference output jack. However, it would be good to read the manual, as they usually cover how those connections work. Otherwise, perhaps someone that owns one could provide further insight. BillWB6BNQ mike cook wrote: Something that must be simple to explain, but that I can't get my head round. I got a new 53230A. When first using it, I measured my T-Bolt 10MHz using the internal 10MHz timebase and it came up short of 10MHz, 9.999 998 5xx. I wasn't worried about it as the counter only has a TCXO internal oscillator. So I fired up my PRS10 and after leaving that on for some time, connected it to Ext Ref. , changed to the ext time base and measured again. This time 10.000.000.00x. Then I switched the two references, measuring the PRS10 against the T-Bolt. Again I got 10MHz down to the 11th digit. All that looked good so I have been using it with either the PRS10 locked to GPS, or the T-Bolt as the external time base. After leaving it on (but not inactive) for a month, I did an Autocal. No problem. I was wondering if that would have changed the internal time base frequency, but no, using that still gave similar figures to the above. So at that point I decided to measure the Internal TB against my reference. So I connected the Int. Ref. Out to channel 1, connected my PRS10 ref to Ext. Ref In, selected the EXT time base and found that the count was 10MHz dead on? I don't get that at all. in summary: DUT against internal TB counts 10MHz.To me that means that the internal timebase is a bit fast. Is that assumption correct? DUT against Ext.Ref counts 10MHz Internal TB against Ext.Ref counts 10MHz. If my assumption above is correct, the count should be greater than 10MHz, no? Can anyone shed any light on that? ___ 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] HP 10811-60165 Double Oven Crystal Oscillator Pin-Outs
I've seen a pin-out for the outer-oven 6-position connector (2 heater wires, 2 thermistor wires), but I've not found anything on the pin-out of the other 6-position connector. Has anyone come across the pin-outs for the 10811-60165 connectors? CS ___ 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] strange behavior of 53230A or is the light on, but nobody in?
TomK, If anyone has technical contacts deep within Agilent, let's see if this issue can be resolved. I would have bought a 53230A when it came out a few years ago but my eval units showed this clock noise problem. That plus the poor quality of the ref out made me think the designers were cutting corners, or had little experience in metrology, or maybe they thought this was ok for a bench instrument. Otherwise it's a really nice counter; the first one from Agilent than can actually do ADEV properly (since it is a time stamping counter). I should dig out my old data and send it to you. Maybe as group we can help them fix the problem. /tvb On Feb 18, 2014, at 12:10 AM, Tom Knox act...@hotmail.com wrote: I have asked Agilent if stock versions of the 53230A and 53132A switched the internal oscillator out of circuit with an Ext Ref signal applied. I thought Agilent's engineer was intentionally vague but said the oscillators were indeed switched out of circuit on the counter with Ext Ref signal applied. These questions were related to several 53132A's I have seen configured with a small board back near the Ext Ref input (OPT H01 I think) that appeared to Switch the internal reference out of circuit. Agilent would not share information on the option. My question to Agilent is why sell an option and be unwilling to say what it does or how your stock unit functions? Thomas Knox From: t...@leapsecond.com Date: Mon, 17 Feb 2014 09:38:28 -1000 To: time-nuts@febo.com Subject: Re: [time-nuts] strange behavior of 53230A or is the light on, but nobody in? Bob, I'm wondering if you (or any else) has measured the PLL performance of the 53230-series? I agree it will clean up the crud but this assumes the ext ref is dirtier than the internal osc. What I found instead was that if you use a good external ref the PLL actually makes it worse. This was very disappointing. The XO version of the counter performed worse than the OCXO version even with a maser as the ext reference. Did your reading of the schematic show a way to directly use the ext ref, bypassing the noisy PLL? The other thing I found was that the ref out signal was a very polluted copy of the ref in. /tvb (i5s) On Feb 17, 2014, at 7:04 AM, Bob Camp li...@rtty.us wrote: Hi If you dig into the schematics (when they supplied them … ): The external reference goes into a phase detector. It’s one of those digital ones that can lock up to many inputs. You could feed 3. MHz in as a standard input as well as 0.5, 1, 2.5, 5, and 10 MHz. The internal oscillator (or an internal oscillator) is phase locked to the external input through a fairly narrow analog loop. The idea is to clean up the crud on the standard line. With no external reference, the PLL drops out and you go back to what ever the local reference is. Yes there’s a little more to it than that and no the circuit is not exactly the same on every counter HP ever made. Bob On Feb 17, 2014, at 7:55 AM, wb6bnq wb6...@cox.net wrote: Hi Mike, The most likely answer is when you select external time base for an input, it disables the connection for the internal oscillator. The external input signal is probably also routed straight to the reference output jack. However, it would be good to read the manual, as they usually cover how those connections work. Otherwise, perhaps someone that owns one could provide further insight. BillWB6BNQ mike cook wrote: Something that must be simple to explain, but that I can't get my head round. I got a new 53230A. When first using it, I measured my T-Bolt 10MHz using the internal 10MHz timebase and it came up short of 10MHz, 9.999 998 5xx. I wasn't worried about it as the counter only has a TCXO internal oscillator. So I fired up my PRS10 and after leaving that on for some time, connected it to Ext Ref. , changed to the ext time base and measured again. This time 10.000.000.00x. Then I switched the two references, measuring the PRS10 against the T-Bolt. Again I got 10MHz down to the 11th digit. All that looked good so I have been using it with either the PRS10 locked to GPS, or the T-Bolt as the external time base. After leaving it on (but not inactive) for a month, I did an Autocal. No problem. I was wondering if that would have changed the internal time base frequency, but no, using that still gave similar figures to the above. So at that point I decided to measure the Internal TB against my reference. So I connected the Int. Ref. Out to channel 1, connected my PRS10 ref to Ext. Ref In, selected the EXT time base and found that the count was 10MHz dead on? I don't get that at all. in summary: DUT against internal TB counts 10MHz.To me that means that the internal timebase is a bit fast. Is that assumption correct? DUT against Ext.Ref counts 10MHz Internal TB against
Re: [time-nuts] HP 10811-60165 Double Oven Crystal Oscillator Pin-Outs
Chris, The 10811-60165 may be similar to the HP 10811-60158 that uses using the following pin-out: 1 - BRN Oscillator Return (Com) 2 - RED Oscillator Power (+12V) 3 - ORG Oven Monitor Return (Com) 4 - YEL Oven Monitor Output 5 - GRN Oven Power (+18-24V) 6 - BLU Oven Return (Com) The following description is from the 10811 A/B Manual where the recommended oven monitor circuit is shown: The Oven Monitor Output is an indicator of oven warm-up. At initial turn-on (warmup) the oven monitor will go to approximately 1.5 volts below the oven power supply voltage. After the oven cuts back, the output will drop to approximately 3.5 volts (at 25°C). The output impedance of this circuit is 10,000 ohms. Richard I've seen a pin-out for the outer-oven 6-position connector (2 heater wires, 2 thermistor wires), but I've not found anything on the pin-out of the other 6-position connector. Has anyone come across the pin-outs for the 10811-60165 connectors? CS ___ 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.
Re: [time-nuts] FE-5680A sweep range setting
Hi, I have a couple that look like the one in these pictures minus the the little frequency control board. http://www.flickr.com/photos/14336723@N08/sets/72157632394339366/ One of mine would not lock so what I did I looked at my other 5680A which is the type referred to in the tip about C217 and looked at how it is connected in relation to the crystal for the VCXO, which is very close to C217. In the ones that I have with the stacked cards this crystal is on the middle card with a little block of foam over it. Near this crystal is a trim cap C245 that seems to be connected the same way relative to the crystal and by adjusting it I was able to get mine to lock, but did find the adjustment to be a bit twitchy and since it is on the middle card, you need to remove the top one every time you want to tweak it a bit. The one that I have are marked with option 57 and instead of having a flange around the edge like many of the telecom surplus ones it is mounted on a piece of 1/4 aluminum plate.The top card has a PIC on it and there is a RS232 level converter chip there but it looks like the connection only go to the 5 pin connector next to the SP232ACT RS232 chip. This one does not require external +5V and in fact bring out the 10MHz on pin 4 where others seem to connect +5V. there does not appear to be any PPS output either. These also have a cutout to expose the 15 pin connector that is on the base board in front of the physics package. Paul. On 2/17/14 11:03 PM, Simon Lyons wrote: Hello everyone, I have a 5680 which is failing to lock. My DDS frequency is 8388608Hz, but it's sweeping between about 8388638 and 8388740. My unit has 3 levels of PCBs in the DDS/VCO corner and there is no trimcap labeled C217. Does anyone know how to adjust the sweep center frequency on this type of 'triple decker' unit? Thanks, =Simon= ___ 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.
Re: [time-nuts] HP 10811-60165 Double Oven Crystal Oscillator Pin-Outs
That pin-out sounds promising as this unit has BLK-RED-BLK-ORG-YEL-GRN-BLU, which seems consistent with the one that you provided. Did you source that from one of HP's various guides or somewhere else? CS -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]On Behalf Of Richard H McCorkle Sent: Tuesday, February 18, 2014 11:07 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] HP 10811-60165 Double Oven Crystal Oscillator Pin-Outs Chris, The 10811-60165 may be similar to the HP 10811-60158 that uses using the following pin-out: 1 - BRN Oscillator Return (Com) 2 - RED Oscillator Power (+12V) 3 - ORG Oven Monitor Return (Com) 4 - YEL Oven Monitor Output 5 - GRN Oven Power (+18-24V) 6 - BLU Oven Return (Com) The following description is from the 10811 A/B Manual where the recommended oven monitor circuit is shown: The Oven Monitor Output is an indicator of oven warm-up. At initial turn-on (warmup) the oven monitor will go to approximately 1.5 volts below the oven power supply voltage. After the oven cuts back, the output will drop to approximately 3.5 volts (at 25°C). The output impedance of this circuit is 10,000 ohms. Richard I've seen a pin-out for the outer-oven 6-position connector (2 heater wires, 2 thermistor wires), but I've not found anything on the pin-out of the other 6-position connector. Has anyone come across the pin-outs for the 10811-60165 connectors? CS ___ 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 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] strange behavior of 53230A or is the light on, but nobody in?
Hi Well at least this got me digging a little. If you grab a copy of the 53230A spec sheet and look under the external reference input, it’s pretty well described. It will accept 1, 5,10 MHz as an external reference. It will lock over a 1 ppm range with the XO option and 0.1 ppm with the OCXO option. Based on that I’d guess they are still using the same basic PLL approach as on the older counters (5335 era). The “Microsoft Windows inside” sticker on the back of the counter was a bit of a surprise …. Bob On Feb 18, 2014, at 11:51 AM, Tom Van Baak (lab) t...@leapsecond.com wrote: TomK, If anyone has technical contacts deep within Agilent, let's see if this issue can be resolved. I would have bought a 53230A when it came out a few years ago but my eval units showed this clock noise problem. That plus the poor quality of the ref out made me think the designers were cutting corners, or had little experience in metrology, or maybe they thought this was ok for a bench instrument. Otherwise it's a really nice counter; the first one from Agilent than can actually do ADEV properly (since it is a time stamping counter). I should dig out my old data and send it to you. Maybe as group we can help them fix the problem. /tvb On Feb 18, 2014, at 12:10 AM, Tom Knox act...@hotmail.com wrote: I have asked Agilent if stock versions of the 53230A and 53132A switched the internal oscillator out of circuit with an Ext Ref signal applied. I thought Agilent's engineer was intentionally vague but said the oscillators were indeed switched out of circuit on the counter with Ext Ref signal applied. These questions were related to several 53132A's I have seen configured with a small board back near the Ext Ref input (OPT H01 I think) that appeared to Switch the internal reference out of circuit. Agilent would not share information on the option. My question to Agilent is why sell an option and be unwilling to say what it does or how your stock unit functions? Thomas Knox From: t...@leapsecond.com Date: Mon, 17 Feb 2014 09:38:28 -1000 To: time-nuts@febo.com Subject: Re: [time-nuts] strange behavior of 53230A or is the light on, but nobody in? Bob, I'm wondering if you (or any else) has measured the PLL performance of the 53230-series? I agree it will clean up the crud but this assumes the ext ref is dirtier than the internal osc. What I found instead was that if you use a good external ref the PLL actually makes it worse. This was very disappointing. The XO version of the counter performed worse than the OCXO version even with a maser as the ext reference. Did your reading of the schematic show a way to directly use the ext ref, bypassing the noisy PLL? The other thing I found was that the ref out signal was a very polluted copy of the ref in. /tvb (i5s) On Feb 17, 2014, at 7:04 AM, Bob Camp li...@rtty.us wrote: Hi If you dig into the schematics (when they supplied them … ): The external reference goes into a phase detector. It’s one of those digital ones that can lock up to many inputs. You could feed 3. MHz in as a standard input as well as 0.5, 1, 2.5, 5, and 10 MHz. The internal oscillator (or an internal oscillator) is phase locked to the external input through a fairly narrow analog loop. The idea is to clean up the crud on the standard line. With no external reference, the PLL drops out and you go back to what ever the local reference is. Yes there’s a little more to it than that and no the circuit is not exactly the same on every counter HP ever made. Bob On Feb 17, 2014, at 7:55 AM, wb6bnq wb6...@cox.net wrote: Hi Mike, The most likely answer is when you select external time base for an input, it disables the connection for the internal oscillator. The external input signal is probably also routed straight to the reference output jack. However, it would be good to read the manual, as they usually cover how those connections work. Otherwise, perhaps someone that owns one could provide further insight. BillWB6BNQ mike cook wrote: Something that must be simple to explain, but that I can't get my head round. I got a new 53230A. When first using it, I measured my T-Bolt 10MHz using the internal 10MHz timebase and it came up short of 10MHz, 9.999 998 5xx. I wasn't worried about it as the counter only has a TCXO internal oscillator. So I fired up my PRS10 and after leaving that on for some time, connected it to Ext Ref. , changed to the ext time base and measured again. This time 10.000.000.00x. Then I switched the two references, measuring the PRS10 against the T-Bolt. Again I got 10MHz down to the 11th digit. All that looked good so I have been using it with either the PRS10 locked to GPS, or the T-Bolt as the external time base. After leaving it on (but not inactive) for a month, I did an Autocal. No problem. I
Re: [time-nuts] strange behavior of 53230A or is the light on, but nobody in?
Thanks Tom and Bob, I have been thinking of contacting Agilent for some time. I think they are a great company with some good products, but there are a few real blind spots in some current products. I also have seen in the past a genuine interest in listening. I would be willing to approach them if I could enlist your help in addressing potential changes to improve the product. Thanks; Thomas Knox From: li...@rtty.us Date: Tue, 18 Feb 2014 18:00:17 -0500 To: time-nuts@febo.com Subject: Re: [time-nuts] strange behavior of 53230A or is the light on, but nobody in? Hi Well at least this got me digging a little. If you grab a copy of the 53230A spec sheet and look under the external reference input, it’s pretty well described. It will accept 1, 5,10 MHz as an external reference. It will lock over a 1 ppm range with the XO option and 0.1 ppm with the OCXO option. Based on that I’d guess they are still using the same basic PLL approach as on the older counters (5335 era). The “Microsoft Windows inside” sticker on the back of the counter was a bit of a surprise …. Bob On Feb 18, 2014, at 11:51 AM, Tom Van Baak (lab) t...@leapsecond.com wrote: TomK, If anyone has technical contacts deep within Agilent, let's see if this issue can be resolved. I would have bought a 53230A when it came out a few years ago but my eval units showed this clock noise problem. That plus the poor quality of the ref out made me think the designers were cutting corners, or had little experience in metrology, or maybe they thought this was ok for a bench instrument. Otherwise it's a really nice counter; the first one from Agilent than can actually do ADEV properly (since it is a time stamping counter). I should dig out my old data and send it to you. Maybe as group we can help them fix the problem. /tvb On Feb 18, 2014, at 12:10 AM, Tom Knox act...@hotmail.com wrote: I have asked Agilent if stock versions of the 53230A and 53132A switched the internal oscillator out of circuit with an Ext Ref signal applied. I thought Agilent's engineer was intentionally vague but said the oscillators were indeed switched out of circuit on the counter with Ext Ref signal applied. These questions were related to several 53132A's I have seen configured with a small board back near the Ext Ref input (OPT H01 I think) that appeared to Switch the internal reference out of circuit. Agilent would not share information on the option. My question to Agilent is why sell an option and be unwilling to say what it does or how your stock unit functions? Thomas Knox From: t...@leapsecond.com Date: Mon, 17 Feb 2014 09:38:28 -1000 To: time-nuts@febo.com Subject: Re: [time-nuts] strange behavior of 53230A or is the light on, but nobody in? Bob, I'm wondering if you (or any else) has measured the PLL performance of the 53230-series? I agree it will clean up the crud but this assumes the ext ref is dirtier than the internal osc. What I found instead was that if you use a good external ref the PLL actually makes it worse. This was very disappointing. The XO version of the counter performed worse than the OCXO version even with a maser as the ext reference. Did your reading of the schematic show a way to directly use the ext ref, bypassing the noisy PLL? The other thing I found was that the ref out signal was a very polluted copy of the ref in. /tvb (i5s) On Feb 17, 2014, at 7:04 AM, Bob Camp li...@rtty.us wrote: Hi If you dig into the schematics (when they supplied them … ): The external reference goes into a phase detector. It’s one of those digital ones that can lock up to many inputs. You could feed 3. MHz in as a standard input as well as 0.5, 1, 2.5, 5, and 10 MHz. The internal oscillator (or an internal oscillator) is phase locked to the external input through a fairly narrow analog loop. The idea is to clean up the crud on the standard line. With no external reference, the PLL drops out and you go back to what ever the local reference is. Yes there’s a little more to it than that and no the circuit is not exactly the same on every counter HP ever made. Bob On Feb 17, 2014, at 7:55 AM, wb6bnq wb6...@cox.net wrote: Hi Mike, The most likely answer is when you select external time base for an input, it disables the connection for the internal oscillator. The external input signal is probably also routed straight to the reference output jack. However, it would be good to read the manual, as they usually cover how those connections work. Otherwise, perhaps someone that owns one could provide further insight. BillWB6BNQ mike cook wrote: Something that must be simple to explain, but that I can't get my head round. I got a new 53230A. When
Re: [time-nuts] HP 10811-60165 Double Oven Crystal Oscillator Pin-Outs
Chris, I bought a number of 10811-60158 so I determined the pin-out from an actual unit. Richard That pin-out sounds promising as this unit has BLK-RED-BLK-ORG-YEL-GRN-BLU, which seems consistent with the one that you provided. Did you source that from one of HP's various guides or somewhere else? CS -Original Message- From: time-nuts-boun...@febo.com [mailto:time-nuts-boun...@febo.com]On Behalf Of Richard H McCorkle Sent: Tuesday, February 18, 2014 11:07 AM To: Discussion of precise time and frequency measurement Subject: Re: [time-nuts] HP 10811-60165 Double Oven Crystal Oscillator Pin-Outs Chris, The 10811-60165 may be similar to the HP 10811-60158 that uses using the following pin-out: 1 - BRN Oscillator Return (Com) 2 - RED Oscillator Power (+12V) 3 - ORG Oven Monitor Return (Com) 4 - YEL Oven Monitor Output 5 - GRN Oven Power (+18-24V) 6 - BLU Oven Return (Com) The following description is from the 10811 A/B Manual where the recommended oven monitor circuit is shown: The Oven Monitor Output is an indicator of oven warm-up. At initial turn-on (warmup) the oven monitor will go to approximately 1.5 volts below the oven power supply voltage. After the oven cuts back, the output will drop to approximately 3.5 volts (at 25°C). The output impedance of this circuit is 10,000 ohms. Richard I've seen a pin-out for the outer-oven 6-position connector (2 heater wires, 2 thermistor wires), but I've not found anything on the pin-out of the other 6-position connector. Has anyone come across the pin-outs for the 10811-60165 connectors? CS ___ 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 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.
