Re: [time-nuts] Thunderbolt question

Thanks everyone. This has given me a lot of things to check as I further investigate over the next few evenings. I'll let you know what I find. Chris > On Aug 5, 2017, at 3:07 PM, Charles Steinmetz wrote: > > Arthur wrote: > >> I’d say it would be an MMIC amp similar

Re: [time-nuts] Thunderbolt question

Arthur wrote: I’d say it would be an MMIC amp similar to this device [Avago MGA-87563] If a chip similar to the Avago part Arthur referenced is what is installed, which seems plausible, the 0.749v on the RF input (Pin 3) is a fault and is caused by an external source of voltage (3.417v)

Re: [time-nuts] Thunderbolt question

On Sat, 5 Aug 2017 10:47:40 -0400 paul swed wrote: > The .5 on the f connector is an issue and thats through the filter on top > of the board made of traces and 3 caps. From Arthur's digging I would agree > he found the chip or one that would work. But that chips voltages

Re: [time-nuts] Thunderbolt question

The .5 on the f connector is an issue and thats through the filter on top of the board made of traces and 3 caps. From Arthur's digging I would agree he found the chip or one that would work. But that chips voltages seem to match so most likely not the issue. What does the F connector measure to

[time-nuts] Thunderbolt question

Pin 1= 0v Pin 2= 0v Pin 3= 0.749V Pin 4= 4.892v Pin 5= 0v Pin 6= 3.417v I’d say it would be an MMIC amp similar to this device. It has the same pin-out so it is a possibility. The Amp In my newer version is an 23 db gain device but 8-pin so I Suspect your version may have similar specs. Here

Re: [time-nuts] Thunderbolt question

Hi, I've changed the blown MMBT3904 in the antenna sense circuit and I still have no 5V to the antenna. I measure 0.5V DC on the F connector. There are two Murata filters (F2 and F3) on the RF path to the antenna. In between the two silver colored filters is a 6 lead SOT package marked 51A.

Re: [time-nuts] Thunderbolt question

Thanks guys. I've opened up my T bolt and noticed a SOT23 packaged part has the top blown off. The PPS BNC jack has U19 beside it. The next part is blown. Could someone take a closeup of the five parts around U19? The intact parts are marked: 5Dz 1AM and two 2Az parts. Chris > On Aug 4,

[time-nuts] Thunderbolt question

Actually that isn't my photo I linked to but one I just Googled. That is probably a board revision most people don't have but it was the first one I saw so I used it just to show that the GPS receiver is part of the only circuit board and not another easily replaceable board like in some other

Re: [time-nuts] Thunderbolt question

Hi > On Aug 4, 2017, at 9:45 AM, paul swed wrote: > > Arthur > Thanks for the picture. I have a TBolt also and its working just fine at > the moment. > But one day it may not. As several people have mentioned lightnings an > issue. > > So going down the crazy thought path

Re: [time-nuts] Thunderbolt question

Arthur Thanks for the picture. I have a TBolt also and its working just fine at the moment. But one day it may not. As several people have mentioned lightnings an issue. So going down the crazy thought path for a moment. It appears from your pix you can figure out what the GPS receiver chip set

[time-nuts] Thunderbolt question

The Thunderbolt is a single board with the GPS receiver in the lower right between the oscillator case and the connectors in the photo in this link. https://www.eevblog.com/forum/testgear/trimble-thunderbolt-gps-disciplined-oscillator/?action=dlattach;attach=102948;image

Re: [time-nuts] Thunderbolt question

At 12:13 AM 8/4/2017, Chris Waldrup wrote: So no voltage out to antenna. I do have one of those 6V max polyphasers but we did get some really close strikes recently. Oh. As someone who lost a tbolt to lightning last year, I feel your pain. I've had to change the Oncore UT Plus receiver

Re: [time-nuts] Thunderbolt question

Couldn't wait till morning on this as it was on my mind this evening. I unplugged the Thunderbolt from the wall and plugged it back in. Immediately the frequency counter attached went from 9.. to zero then when it was powered back up went to the other side of 10 MHz at 10.000 and

Re: [time-nuts] Thunderbolt question

Thank you Didier. I'll check tomorrow for further issues. Chris > On Aug 3, 2017, at 10:05 PM, Didier Juges wrote: > > "If the Thunderbolt loses satellites, does it still put out a 10 Mhz > signal?" > > Yes of course. When that happens, the Thunderbolt is said to be in

Re: [time-nuts] Thunderbolt question

"If the Thunderbolt loses satellites, does it still put out a 10 Mhz signal?" Yes of course. When that happens, the Thunderbolt is said to be in holdover. On Aug 3, 2017 9:29 PM, "Chris Waldrup" wrote: > Hi, > > I just noticed the laptop that is always connected to my

[time-nuts] Thunderbolt question

Hi, I just noticed the laptop that is always connected to my Thunderbolt had a yellow block under COM1 on the Tboltmon program where it normally is green. Also the date up on the screen was in early July. Satellites were still shown. The counter I leave connected still shows a 10 Mhz output.

[time-nuts] Thunderbolt Question

I have been using a surplus Thunderbolt for about six months, and it seemed to be working fine. In January 2012, a message came up in yellow, (LEAP PENDING!), I don't know what this means, but since it didn't go away on Feb 28, must not be leap year related. About a week ago I got a Holdover:

Re: [time-nuts] Thunderbolt Question

Maybe it's the antenna, or a short in the cable (water in the coax) or a nearby transmitters that is jamming the GPS signal. The simplest way to diagnose the problem is by swapping parts.Is your antenna in a good location with a direct view of the entire sky? On Mon, Apr 23, 2012 at 9:05

Re: [time-nuts] Thunderbolt Question

There is a leap second waiting for June/July this year. On Mon, Apr 23, 2012 at 6:16 PM, Chris Albertson albertson.ch...@gmail.comwrote: Maybe it's the antenna, or a short in the cable (water in the coax) or a nearby transmitters that is jamming the GPS signal. The simplest way to diagnose

Re: [time-nuts] Thunderbolt Question

I have been using a surplus Thunderbolt for about six months, and it seemed to be working fine. In January 2012, a message came up in yellow, (LEAP PENDING!), I don't know what this means, but since it didn't go away on Feb 28, must not be leap year related. Hi Ed, Right, in this case the

Re: [time-nuts] Thunderbolt Question

Ed, the message about leap pending refers to an impending leap second, in June I think but others may know more... It will happen and the message will go away. From your LH screen, I would say that your signal levels are way too low. I don't know why, perhaps low antenna gain, a badly sited

Re: [time-nuts] Thunderbolt Question

On 04/23/2012 07:01 PM, Tom Van Baak wrote: I have been using a surplus Thunderbolt for about six months, and it seemed to be working fine. In January 2012, a message came up in yellow, (LEAP PENDING!), I don't know what this means, but since it didn't go away on Feb 28, must not be leap year

Re: [time-nuts] Thunderbolt Question

Not yet Marcus- that sort of technology will come right after the ftl drive, but just before we start building a dyson sphere.. On Tue, Apr 24, 2012 at 7:00 AM, Magnus Danielson mag...@rubidium.dyndns.org wrote: I thought someone finally put a cesium on the step motor keeping the ear

Re: [time-nuts] Thunderbolt Question

wa6...@comcast.net said: I have been using a surplus Thunderbolt for about six months, and it seemed to be working fine. In January 2012, a message came up in yellow, (LEAP PENDING!), I don't know what this means, but since it didn't go away on Feb 28, must not be leap year related.

[time-nuts] Thunderbolt question regarding PPS and 10MHz phase relationship

It can be altered, but only by 50ns. You can invert the phase of the osc sense (feature not available on Thunderbolt-E or Thunderbolts built before March 1998). Use the '^' command in Lady Heather. The PPS output is synchronous with the 10MHz signal

[time-nuts] Thunderbolt question regarding PPS and 10MHz phase relationship

Hello all, I'm trying to adjust the time between the leading edge of the PPS square wave and the 10MHz zero crossing outputs on a Trimble Thunderbolt. The manual seems to indicate the cable delay compensation setting will do this. As I understand things, this is also called the PPS Offset in the

Re: [time-nuts] Thunderbolt question regarding PPS and 10MHz phase relationship

Bob Robert Darlington wrote: Hello all, I'm trying to adjust the time between the leading edge of the PPS square wave and the 10MHz zero crossing outputs on a Trimble Thunderbolt. The manual seems to indicate the cable delay compensation setting will do this. No, it doesnt. This only

Re: [time-nuts] Thunderbolt question regarding PPS and 10MHz phase relationship

Ah ha! That explains the changing numbers I see on the 5370B (jitter), and explains why I see no change on the scope other than the jitter. Reading the manual, I don't see any clear explanation like what you just gave me. I see my mistake in manual interpretation but not until after reading

Re: [time-nuts] Thunderbolt question regarding PPS and 10MHz phase relationship

Bob One way of reducing the effective noise/jitter on the PPS signal when using it with the 5370 to measure the instability of a source with respect to the Thunderbolt is to use the PPS to ARM the 5370 whilst the 10MHz from the thunderbolt starts the 5370 and the source (or a frequency generated