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A little shade

Mar 28

Posted by cdc in General Interest, Technical Stuff | 2 Comments

Here’s visual evidence of the effect of a small amount of shade on a PV array. This is why your installers won’t recommend putting panels where there’s a chimney or a tree. In our case, ONLY for half an hour or so in the morning at this time of year, next door’s roof shades a corner of our array.  As you can see from the picture, we have 14 panels, and the shadow is covering a total area of about 1.3 panels.  Now have a look at the graph below, which is the inverter out put for the SAME day as I took the photograph. The peak output during that day (27th March 2012 – sunny all day, not a cloud, no haze) was 2.56Kw. I took the photograph just after 9am, and as you can see, at that time, the output was barely 250-300W. You can see the vertical leap from there to around 2.2kW when the shadow finally moved off the corner of the panels.  So even though the shadow was covering only about 10% of the total area of the array, the power output was cut by about 80%.

If I blow up the neighbour’s house (I’ll wait until he’s out of course!) then the extra power I’ll get off the roof on a day like this is indicated by the “missing” area on that graph – if you imagine a smooth curve from the zero line at around 7am when the sun first hits it joining up with the curve going on from the top of the vertical leap, the curved triangle you get is the amount of power the roof’s shadow cost.

So if you have a chimney, tree, or similar, whose shadow will move across the panels during the course of the day, don’t put panels there…

 

123-reg – a warning.

Sep 8

Posted by cdc in Soapbox, Technical Stuff | No Comments

We host domains for our clients. We don’t have a pretty webby control panel for them – we find most of our customers prefer to administer their domains by phoning or emailing the required changes to us and having us take care of the fiddly techy details.

But we have some customers who prefer to host their domains elsewhere. Which is fine by us. And we still help with advice on what to do when changes are needed.

Today we are switching a customer to a new ADSL network and as their incoming mail is delivered directly, that means a new MX record. We sent the client the info they would need to add to the domain, which is hosted at 123-reg.

During the process we suggested that they add records to allow our own name servers to be “secondary” (or “slave”) servers for the domain. That means any changes to the domain would be advised to our servers at once!

Adding secondary servers should just be a case of adding two new “IN NS” records to the domain’s existing NS records. The existing ones point at the 123-reg servers, of course.

However, adding two new NS records permitting the Wizards dns servers to request updates from the master, broke it – because on adding these records, 123-reg’s system assumed that they were meant to be taken INSTEAD of the original ones (though our client did not delete the original ones).  So within minutes she’s getting phone calls saying “we can’t send you emails, they bounce back”.

On re-visiting the 123-reg control panel, she finds that the wizards DNS servers are now the ONLY NS entries.

On returning the NS records to what they were before, we further discover that to back up their invalid assmption that we wished to CHANGE name servers, not add more, they’ve deleted all the A and MX entries for the domain.

On painstakingly re-creating all these (fortunately we had notes on what they should be! A good idea, folks if you maintain your own domain configs) 123-reg made a further assumption – that we would want the client’s emails sent to the 123-reg email servers. So it had added two MX records for that to the ones we had set up. Good job we went back and checked it *again*. So finally these extra MX records were removed, and finally the domain is… back where it started!! Only now the client will not receive any email from her regular co-respondents until their local DNS caches have expired, which will be around 8 hours, or, a whole working day lost!

Thanks, 123-reg.

 

Gentle reader, if you host your domain with 123-reg, please take note that any time you make a change, it appears that 123-reg computers may look at your change then make some wild assumptions about what you really meant, and make further changes which you are unaware of. After you’ve made the chances you want, please, log BACK in a few minutes later and review the now current settings just to make sure they are what you wanted them to be!!

 

 

Fibre at last

Aug 25

Posted by cdc in Soapbox, Technical Stuff | No Comments

I’m pleased to say that today we saw the FTTC (bt fibre internet) go live for a customer who actually needs it! Out miles from the exchange, they could barely get ADSL at all, and only at very low speeds with poor reliability. Today they have fibre. Advertised at up to 40 mb/sec, they’re only getting about 7 mb/sec, coz they’re also a long way from the street cabinet, but that’s still a lot faster, and hopefully more reliable, than they had before.

The really good news is that they could get it at all – as despite the fact that this technology is intended to help bring broadband to people in remote locations who can get no ADSL at all or only poorly, BT have chosen to recoup their development costs by installing it first and foremost in busy urban locations as “faster”. They advertise it on telly (under the name “Infinity”) and tell you how much more wonderful it will be for your online TV viewing and those poor folk who live on the top of a hill in nether-shire, still can’t even get email.

Well, I’m at least pleased to say that though rural locations don’t appear to be on the radar yet, BT do appear to be accelerating the installations of new FTTC/FTTP enabled exchanges, and more and more folk are able to take advantage of it every day. If you want to know if that includes you, give us a call!! 01494 837515.

Print process – FinePrint

Jun 20

Posted by cdc in Technical Stuff | No Comments

I’ve been doing clever stuff with Word this last ten days that I’ve not done before. Well, not quite true. I was – 20 years ago! And it’s depressing how advanved Word 2010 is *not* compared to Wordstar.

First up I needed to write a letter to 250 of my customers. The names and addresses are all in a database, so I thought, quick mailmerge.

Well, I had the letter drafted in half an hour and I dropped in the Contact name, Company name, Address, etc., and ran a preview merge. And saw honking great gaps in the address. When an address field is blank, it doesn’t close up.  I daresay there’s an option to do it somewhere but it wasn’t as simple as clicking on the field and setting a “don’t print if blank” option from a flyout menu. That would be modern and trendy.

Then I found the “Address Block” variable. Ah – this seemed to do what I wanted. Only after the first batch of letters was folded and sstamped and in the post did my associate notice that the “City” name was missing.  This eventually turned out to be because Word naturally assumes your data will be Addr1, Addr2, City, State, Zip., where we had Addr1, Addr2, Addr3, Addr4, Postcode. It had worked out for itself that “postcode” was good for “zip” but for some reason had made NO such assumption about “Addr3″ and “Addr4″.  But I finally, at least, found a way to tell it so it’ll work next time.

Today, I needed to print out the newsletter for our 4×4 Response Group. I’ve been sent an 8 page Word document. No sweat. Power up the colour laser, click Print… OK, I can print Odd Number Pages, then Even Number Pages. But like most modern printers my laser prints documents in “normal” reading order, and doesn’t offer a “print in reverse” option. So I’d get Page 8 on the back of Page 1, Page 6 on the back of Page 3, etc.

Ah – there’s a “manual duplex” check-box. I check it. I print one copy (hey, been burned before). Sure enough it prints pages 1, 3, 5 and 7. It tells me to take the output stack and feed it back in. Click OK. Ah, it says it’s printing 2, 4, 6 and 8 but surely it’s smart enough to be sending them out backwards….. Nope, it’s done exactly the same as if I’d used the Odd Numbers / Even Numbers options. Bin that. Good job it’s paper recycle collection day tomorrow.

So Liz tells me her HP inkjet has an option in the driver to do duplex, it tells you when to feed the output stack back in, how to orient it… and I find so does mine! Except taht it doesn’t bother to stop for you to flip the stack so you get another supply for the recyle man.

So, FinePrint to the rescue.  This is a fabulous little utility that I’ve been using for abotu ten years. It has saved a fortune in pre-printed letterhead. I just buy plain paper (better quality for letters, but still plain) and the output from Word, or our invoicing system, or, whatever, goes to FP which adds our letterhead, or my personal letterhead, or, lately, cleverer stuff like a direct debit mandate form with required logos, etc., in the right place, then sends the combined document to the printer.

I tend to forget it can do other things too. I had remembered taht it could print a document two- or more pages on a page, so compress an A4 so it prints as 2xA5 documents per page. IN fact we used to use this to print file copie of our invoices four to a page to save paper and toner (now we don’t print file copies – we keep the data, we can pritn them on demand).  One neat trick is “boolket”. It prints a couple of test pages andf asks me which way they came out, so it learns how my printer works. Then it does just what both Word and the HP driver’s built in s/w failed to do – prints the top of each page, then, the right way around and in the correct order, prints the backs, all I have to do is fold them up and hand them out!

So – my tip for the day, whatever you print, check out FinePrint.

Sync that Android

Jun 8

Posted by cdc in General Interest, Soapbox, Technical Stuff | 1 Comment

Having an HTC Android phone has lots of good points. But one of the things which constantly has me tearing at what remains of my hair is trying to sync the data with my PC.

I even switched from my old mail system to using MS Outlook to avoid any possible issues of compatibility with “less popular” software.

The problem, as I’m sure more than a few of you know, is that you plug the phone in, you select “Sync” on the phone, and then, after a delay, it says “can’t find HTC Sync on your PC. Would you like to install it?” And, of course you know HTC Sync is not only installed but is running.

Thing is, it *isn’t* running, not any more. It might’ve been last time you synced half an hour ago or last week, but not any more.

Well I think I’ve found a trick to make it work, without having to totally reboot the machine. Especially these days, with XP or Windows 7, unlike the bad old days, you don’t HAVE to reboot windows every day, and, in fact, I get cross if something makes me reboot it more often than once every couple of months.

Here’s the trick. Please let me know if it works for you, or if you find a quicker way.

  • Unplug the phone from the PC
  • Close the HTC Sync app
  • Using Task Manager, kill the process called CapabilityManager.exe
  • Similarly kill the process called ClientInitiatedStarter.exe
  • Finally, kill the process called FsynSrvStarter.exe
  • Now close task manager.
  • Re-start HTC Sync from the Start menu (or your desktop icon) in the normal way.
  • Connect the phone, and tell it to sync.
  • Cheer. For it will work. I hope…

I shall experiment further and find out if the trick can be accomplished by killing just one of these modules, coz I assume it’s a bug in one of them that causes the problem.

It’s a pity HTC wont’ admit to the existance of the problem and fix it. (Well, I say they won’t, I can’t find any reference to it on their website, FAQ list, etc.)

 

Is it really that long?

May 27

Posted by cdc in General Interest, Technical Stuff | No Comments

It seems like only a few months ago since I signed up to use an online service, but it was years before “the internet” as we know it today. CIX predates the lot! In fact, the first widely accessible “public” internet access available to UK consumers, a dial-up service offered by Demon Systems, was conceived and planned in part in discussion groups on CIX, and was set in motion only after a working number of potential customers had been recruited mostly amongst the CIX userbase.

This week, CIX has a new owner! I’m not going into details cos Wendy Grossman has already waxed lyrical – follow this link to her article.

If you want to ask me why I’ve stayed so long and why I still think it represents one of the best resources on the modern internet despite being a little antiquated (though I daresay this will now change) ask me here..

The tube in detail.

Mar 29

Posted by cdc in General Interest | No Comments

If you’re even remotely geeky about trains and railway networks, this is worth a look. It’s a “geographical” map of the London tube network, it includes all current lines and stations, but also all historical lines, stations, part-built stations, etc., and it shows sidings and train yards, etc.  It’s geographically accurate, it shows where the lines actually run, including where they cross each other (e.g. the diving pass the Victoria line makes just south of Warren Street), the turning loop at Kennington, the way the platforms are staggered at Picadilly…

Just as much a work of art as the “traditional” tube map is often regarded.

 

Bank website security starts with the banks!

Mar 14

Posted by cdc in Technical Stuff | 1 Comment

Copy of an email I just sent…

Dear Barnsley Building Society.

I received an email (see below). Clearly a phishing attempt, I thought, as it contains a clickable link. No sensible email from a bank or building society would contain a clickable link.

Trouble is, it looks like a real link.
Tell me you’re not sending out emails with clickable links in. Have you heard of “phishing”?

Oh noes! We’re all going to glow in the dark. Or not…

Mar 14

Posted by cdc in In The News | No Comments

Perhaps not, actually.  What’s really going on in those Japanese nuclear power stations?

 

Here is a post with actual *facts* instead of just scare-mongering paper-selling headlines.

 

https://morgsatlarge.wordpress.com/2011/03/13/why-i-am-not-worried-about-japans-nuclear-reactors/

Exchange Server FQDN setting

Feb 8

Posted by cdc in Technical Stuff, TidyMail | 1 Comment

As ISP servers are having to be made harder and harder to reject spam, more and more people are finding that badly configured systems start to have their mail rejected.

A very common fault is failing to set the name that a Microsoft Exchange Server uses when it initiates an SMTP conversation across the internet. The HELO parameter of a conversation used to be logged and ignored but these days it’s very common indeed for servers to check the parameter makes sense.  One of the things they will do is check that the name can be looked up on DNS.

If you don’t tell your Exchange Server what name to use, it’ll make one up using it’s own name and your local network name. Commonly, this will be something like mailserver.fredbloggs.local . Microsoft have long recommended using a .local domain name for internal networks and this is one of the results. Sadly, a .local name means nothing to the rest of the internet (that’s why you use it) but this means you have to provide the “Glue” by which external (i.e. anyone outside your network) servers use to confirm you are you.

It’s a simple configuration change you should only ever need to make once, and it won’t affect how your server behaves within your local network. It just changes how your server introduces itself to other people’s servers when it connects to them to try to send emails.

  • Start ESM
  • Go to Servers -> Protocols
  • Select Default SMTP Virtual Server Properties
  • Go to Delivery tab
  • Click Advanced Button
  • Fully Qualified Domain Name – put what the outside DNS hostname is here – e.g. mail.fredbloggs.com
  • Restart SMTP Service.

NOTE that you should try to ensure that the “reverseDNS” for the public IP address of your mail server matches this too. At the moment its common to check that there IS an IP address for the name given, in future it will be more common to check that this IP address is the SAME as the IP address from which the connection is originating. SO if you can’t get your ISP to change your ReverseDNS entry to match mail.fredbloggs.com, then it may be necessary to find what they DO give as your ReverseDNS (e.g. adsluser123.isp.com) and make your FQDN match that.