Saturday, 16 May 2015

Using Remote SDR's

A recent post to Yahoo's Perseus SDR Group posed some interesting questions.

Lasse, SM5GLC, operates an online remote Perseus and made the following comments:

Over the past few weeks/months I have see some "power-users" on my Perseus server... and my plan was to dissect the server log to investigate the usage percentage of my server... and found that already in May the log is 240 kb and growing fast. It seems impossible to analzye by hand.

Now I do notice one user, not too far away (only some 200 miles or so), seems to spend 2-3 hours per day using my server. Mostly just use all allotted time and then get back on asap. I know my antenna is nothing to write home about and the performance is mediocre if any... so this makes me wonder. What on earth do this user do with all the time??

Do others see similar behaviour??

By browsing the log it seems most, user time,70-80 per cent, are from Russia. Most others stay only for a very short period of time, up to a few minutes.

Has anyone tried to hack a script that would automatize the log analysis?? 
A few Q's that I do have are:
Is the server abused by some?
What is the optimal allowed time? and then the drop-out time?
What usage load would be best to shoot for??

Don, VE6JY, a long-time remote owner added:

I notice similar patterns here.  Obviously some are listening to a single frequency for the entire time, others stop by for a few seconds to see if a certain target is being propagated.  And then some just tune around and see what there is to hear and see. And I'm sure some fall asleep until it times out. These are all things I have done when I am using the remote side.  One thing we need to remember, an antenna that is mediocre to one person may be a window to the world for someone living in the urban noise jungle.  And consider this - if there were enough remotes to choose from, scattered all over the globe,  even a poor antenna would cover their locals and fill in the gap.  Unfortunately, the number of remotes seem to be dwindling, esp here in N AM.  Maybe summer coming and lightning season but still, even this winter, choices were fairly meagre. 

I'm not too concerned about the usage aspect - it's not a big drain on my internet and I see enough different names, many of whom I know personally who use it so I think most get a fair chance to see if whatever signal they're looking for makes it to my part of Alberta.  Both of mine are set to 62 mins on with the minimum 2 minute reconnect time.

The only "abuse" if it really is, I see sometimes is from the amateur radio side, people wanting to hear a station better in order to work a rare one or have an unfair advantage in a contest. What does annoy me is users who can't be bothered to put in their proper name or callsign or even a lat/long. And then there's a few servers that get the lat/long wrong or reversed so they wind up in a rare portion of the world and for a moment we all get excited!!

Both operators raise some interesting questions!

If you have used a remote SDR or do so with some regularity, how did you find the experience? What types of things did you listen or look for? How much time would you typically spend on the site? What do you think the limits on time should be?

I have used a remote once or twice in the past, to listen for my Tri-Tet-Ten's chirpy, low power signal, and found it very useful but I've never used one for general listening.

What are your experiences?


John said...

The few remote receivers I have used are the
one in Utwente NL and K2SDR NJ USA that use HTML5
The site has a nice collection

Does the VE6JY receiver use HTML5? Can someone
post the URL.

Others seem to always be busy or a complex log in
is required

Anyone have a URL for 80m and 160m receiver within
1500 km of Vancouver BC


Steve McDonald said...

Hi John ...the VE6JY SDR is a Perseus but I believe you can download the interface software that will let you use these receivers. Here is a list of them: