Manuals, Timing, Ham Radio, Test Equipment

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This site has been operating since the late 1990's. While it started with manuals I had scanned myself, most manuals available today have been submitted by users and visitors of the site. 

From the beginning and until September 2014, the site was hosted on various "shared hosts". This refers to services where many, hundreds or even sometimes thousands of sites are hosted on a single computer (and behind a single IP address). 

After trying a few such services, I had settled on 1and1.com. They have been generally good. The site has had good availability and downloads have been speedy. However, as the traffic has grown (to a monthly average in excess of 2TB as of 2014), I have been informed that I would have to either upgrade the service, reduce the amount of downloads to about 10% of what it has been, or be shut down. You can see some statistics of the amount of data that the site delivers here: Statistics.

The site is now hosted on a higher class of service called Virtual Private Server. These are virtual private machines hosted on very powerful computers. Virtualization software allows to run multiple instances of virtual computers and allocate adjustable amounts of resources to each. Unlike a shared host, where multiple users share a single installation of the Operating System with limited rights with regard to Operating System settings, VPS grants each user his or her own dedicated copy of a machine on which you have your own operating system installation. A side advantage is that I have a dedicated IP address. 

My current host, MyDomain.com, allows me to adjust the amount of resources (RAM, disk space, number of CPU cores, bandwidth) on the fly without as much as having to reboot the machine. Of course, the price is adjusted accordingly and in real time. 

However, this more advanced setup has two significant drawbacks: it costs significantly more to rent a VPS than a shared host and I am completely responsible for the computer's management. This has advantages: I can do pretty much anything with the machine within the limits of my hosting agreement. I can install any software package I want and have as many email accounts as I want. However, I have to manage all these features by myself. All these security breaches you hear about are due to software weaknesses that have to be regularly patched, sometimes urgently. This means that a significantly higher fraction of my free time will be spent dealing with sysadmin issues. Not being retired (and with no immediate prospect of doing so), that means that my life just became a little more complicated and busy. 

Those who have been visiting the site for a while probably noticed the appearance of an ad banner at the top of most pages a year ago or so. This is a Google AdSense banner. It has brought welcome but modest revenue, barely able to offset the cost of the previous shared host. I surmize this may be due to the fact that most of my visitors are like me, thrifty :) and they have little interest visiting the pages of the advertisers.  

So, at the suggestion of many satisfied users, I now also display a Paypal "Donate" button at the top of each page. Should you feel so inclined, you can express your appreciation by using the button as many times as you wish. No amount too small or too big. 

I have enjoyed managing the site. The occasional thank-you emails I get are all the encouragement I need, keep them coming :)

Thank you for your support, and do not forget, those manuals you just downloaded have most likely been uploaded by someone like you, so if you come across public domain manuals (test equipment, ham radio or timing related) that I do not have, feel free to upload them. 

For more information on copyright issues and my position about it, please check the Copyright and the Manuals Copyright pages.

Didier Juges KO4BB, site owner and sysadmin.