Sunday, April 17, 2011

Time to ditch Dimension 4

Digital modes such as WSPR and JT65A are time-synchronous and require the computer clock to be accurate to within a second. New users frequently don't realize this and find that they aren't decoding any signals. When they go to a forum for advice they are inevitably advised by well-meaning helpers to run a bit of software called Dimension 4.

Once upon a time there may have been a good reason for using this program but today it is not a good idea at all. I have seen several forum threads where people have installed Dimension 4 and believed that their PC clock was now accurate, but were still not decoding signals. I suspect that this is because newer versions of Windows have tightened the security controlling whether programs are allowed to do things like change the system clock. Dimension 4, being last updated in 2004 according to its website, knows nothing of this.

There may or may not be ways to make Dimension 4 work under Windows 7 or Vista but there is no reason to bother with them. Instead, just install Meinberg NTP for Windows. Not only is this every bit as free as Dimension 4, it is also the official Network Time Protocol client software. Nothing is ever going to keep your computer clock more accurate than this, and if installed using the default settings it will "just work" even on the latest versions of Windows.

So please, computer Elmers, stop telling people who need to get their clocks synchronized to install an old and unsupported program.

16 comments:

PE4BAS, Bas said...

Ok Julian, you made a point. Although never had any problems with D4 on XP and VISTA. You're rigt about being a outdated piece of software. Will try NTP later on the day...73,Bas

VE3WDM said...

Good morning Julian, I have just switched from D4 to NTP and it works great. It's nice to have the window that can be pulled up so you can watch the progress of NTP with it's connections. I also printed off the manual and will be reading it over this week.

SV9OFO said...

me no expert, but isn't "Automatic NTP syncronisation" of windown XP and on sufficient for time sync?

Julian said...

No. If you are referring to the built-in time sync, I think it runs only once a week or once a day. Many computers drift too much for this to be adequate for this kind of radio use (though it's fine for file time stamps etc.) The clever thing about NTP is that it works out the computer clock drift and applies compensation in real time so the clock is always accurate to within 1/10 of a second or so.

SV9OFO said...

Wow.

I learn new things today.

Well, I think there is a need for oven-controlled motherboards... hihi.

That is, cause if you attempt to operate WSPR mobile on a remote location you would have the absolute need for a 3g internet connection just for the NTP time accuracy connectivity, which is a total fail in terms of independance from public infrastructure, ie in emergency or just to be all you can be on your own.

Maybe some cesium clock source could be handy... especially having some USB connectivity... hmmm. But hold on... Ins't GPS a precise global time base source, anyway?

Food for thought.

73

Julian said...

Yes, of course, many people use a GPS source, especially for high accuracy. I believe that a standalone WSPR beacon project someone built used GPS for the timing. But NTP is good enough and free if internet access is available.

Fenris said...

It is quite straightforward to set up Windows to use multiple time servers and change the intervals between corrections, see here:

http://www.cumps.be/nl/Blog/Read/howto-set-up-ntp-on-windows-vista

I tried to get the Meinberg NTP client to work on my W7 64 bit laptop, it resolutely refused to work, presumably because of permissions issues.

The instructions posted above work for me, and keep the clock accurate.

Paul PC4T said...

Hello Julian, I work with Dimension 4 with XP and now with Win 7, without any problems. I tried Meinberg NTP, but it fails to work... to complicated for a simple man like me. Never change a winning (working) team, they say, so I stick to Dimension 4. 73 Paul

John said...

Hi Julian, Dimension 4 with XP works fine for me at the moment. Thanks for the info 73

Anonymous said...

Also one of the "D4 works for me OK" team :-)

M1AVV said...

I've been using About Time which hasn't been updated since 1999. This even works with Windows 7.

Greg said...

Good advice. I am using Dimension 4 for WSPR on Windows XP. But I'm transitioning to Windows 7 and I simply could not get Dimension 4 to work there. I just installed Meinberg NTP and it works without any fuss.

I'll second your advice about not using Dimension 4. I would be very wary of using any system-type software that hasn't been updated since 2004. The operating system environment has changed drastically since then, so the risk that the software won't work right is very high. Windows Vista and 7 are entirely new operating systems, and Windows XP has had so many service packs and other patches that it is also quite different now.

Heiko said...

Hi Everybody!

This is Heiko Gerstung from Meinberg, I am the maintainer of the NTP Installer for Windows which Julian mentioned in his post (thanks for that!). Since we are always interested to improve our installer, I would like to find out why it did not work for some of the commenters.

We are not only providing the software for free, we also offer free support for it, so please let us know if you faced difficulties with the installation of NTP on your PC and if you are willing to provide debugging information (such as log files, software version information etc.).

Our NTP support team can be reached at ntp-support@meinberg.de !

73,
Heiko

Waynomo said...

So just upgraded from XP to Windows 7. I have been using D4 for years and had been very happy with it. I have installed NTP on my Win 7 machine per Julian's recommendation (TY) and it appears to be working. The problem is I don't understand how it is working or what exactly it is doing on my PC. How does it keep my PC clock accurate? Does it just update the time in the background? How often does it do that? The Windows adjust/time date is still set to automatically synchronize. Does that matter? (I have never been happy with the frequency of that service.)

Thanks for any feedback.
Wayne

Julian Moss said...

Wayne, I think the NTP developers would be the best people to answer your questions, but I think NTP works out the amount of correction your computer clock needs and then applies it in regular increments.

The Windows time/date synch checks once a week (or something like that) and applies a correction. It is intended to keep the clock accurate enough for file timestamps, the scheduler and things like that. It should be disabled (which I think the Meinberg installer offers to do automatically.)

Julian, G4ILO

Waynomo said...

The Windows Time service was automatically disabled. The automatically synchronize function under adjust date/time was not disabled. I disabled it and mis-set the time and the time did correct after a bit. I suspect it doesn't matter if is the Windows function is left running. It's once a week correction can't muck things up too badly.

TY!