Freeing up spectrum is the motivator for closing down analogue TV - around half a dozen digital stations will fit in the bandwidth needed by one analogue station.

If the need for spectrum gets so desperate that they need to hijack some from amateur allocations it won't be a few kHz here and there - they'll just take entire bands.

I'm sorry but I can't buy into the idea that the FCC (or any other national body) will insist on using any specific transmission method.

Thanks for this info.

I finally got around to trying the software from there last week. It doesn't seem to crash but both I and my son (M0XDK) had a situation where it was reporting huge rainfalls when there was none.

I cleared out all the datafiles from the PC then restarted it and haven't seen this bug again. I think XDK is still suppressing his rain measurements though (maybe he's afraid the Air Sea Rescue helicopter will turn out to save him )

Google indexes websites better than they index themselves.

http://www.iht.com/articles/2008/04/17/america/17clothesline.php

Well from the reply I think it's highly likely the miltary producing the interference in some way...

"The army barracks is only ~100m away. It's very very close, I can see it from my kitchen window."

Hi Jerry,

thanks for the reply. I've posted a link to this thread and copied your reply over there. Either the poster will register here or I'll post back the answer to "how close".

The thing that doesn't jibe with me is why the military would be using 1600KHz - I'd have expected them to mostly be using vhf/uhf for close range stuff and maybe satellite comms for distance.

Mark

If you don't get any replies on this one I'd suggest that the easiest option would be a reset to manufacturers defaults which will be in the manual somewhere.

This one is from an ADSL forum. Somebody there has noticed that he gets periods of interference which cause high error rates and a fall in snr.

He has tracked the noise down as appearing at around 1600Khz (he is on ADSL2+) and recorded it. He hasn't had any luck DFing it but with only a MW radio and no experience that's not especially surprising.

I've only recently started to rebuild a station after many years of inactivity. I've had a listen and can't even start to guess what it may be. Part of the time it sounds like it may be data but the characteristics vary during the fairly short recording period. He didn't retune at all.

He mentioned that he does live close to an Army barracks which may well be relevant.

Now I reckon you folks must have heard just about everything on air and may be able to help here. This is an MP3 of the sound...

http://www.smsmasters.co.uk/1600khz.mp3

Any thoughts appreciated.

I'll ask here as I suspect the TMD700 is a lot more commonly used by those interested in APRS.

I use a TMD700E mobile.

I bought this rig on eBay and initially it used to power itself up when it got voltage on the power cable. I reversed a broadband receive mod which seemed to be stopping more useful features like auto repeater shift. Doing this causes a master reset back to defaults. After it I found I always needed to power up the rig manually. There isn't any menu option that I can see so I just accepted that's how it works - maybe the broadband receive mod altered that too.

I use a boom mic with a PTT switch mounted on the seat as it won't fit on the gearshift. I occasionally catch this when getting out but have always noticed in the past. The other day I didn't and the rig was powered up with PTT on. I noticed the switch position when I got home. The rig was not in transmit and sfaik never was. Since then the rig once again powers itself up whenever voltage is applied.

Has anybody else seen this behaviour? Is it documented somewhere and I've missed it?

I have ...

http://www.db0anf.de/app/aprs/stations/weather-G6KIZ

The big gap was due to an ISP problem which prevented me connecting to the APRSserv network.

The supplied software produces and ever increasing CSV file. I've set up a bat file for UIView to run which runs a home constructed script to reformat that for UIVIEW and crop it down to a reasonable size. The problem is I've done it to suit me with software to hand which means it will be pretty useless for other hams - I have a text editor Kedit32 which can run REXX so that's what I used. It should be a simple project in any language though as it is only a question of reformatting some data.

I've put a few bits and bobs on http://www.digitalham.co.uk in the APRS and equipment sections on this unit. It's easy enough to work out what each data field is just by looking but the php script I used to use to display the data until I found the excellent DB0ANF site should make it clear what is what should you get stuck - thats on one of the pages in digitalham.

When I complained about some faults with the unit and mentioned the software was buggy W&S did say there would be a software update - trouble is they didn't say exactly when or where to get it

You need a Comet CHA250B http://www.eham.net/reviews/detail/5175

As an alternative to buying one you could add a short length of wire to the "hot" side of your dummy load which is apparently how that one operates.

I think 10m is more or less dead these days so your session is unlikely to cause any inconvenience if conducted through a normal antenna. Plus your usage is well within the terms of any amateur licence.

This is a long shot. I don't own or know anything much about the TS50. I do own a TS2000 though and found that was running low o/p on one band at least while others were fine.

I see that the TS50 looks like a modern computer controlled rig just like the TS2000.  Now the TS2000 has lots of knobs and buttons not to mention umpteen different menu settings and I bought it secondhand - I haven't used it much yet and really don't know my round the thing so I decided to reset it to manufacturers defaults (look in the manual - usually hold a key or two while powering up).

That fixed the low output problem. It may not fix the TS50 but it will certainly lose all the programmed settings and memories so it's not a totally no-cost option.

I have never made one but I have read up a bit on 5/8 waves and picked this up (which could always be wrong naturally as the antenna world seems to be full of contradictions and argument)...

A 5/8 wave is non resonant and a balun isn't going to cancel the reactance.

The length is chosen mostly to provide a convenient match to 50ohm with an iffy ground which is why they get used as mobiles. A 4:1 balun is going to make that worse.

For my money if you've found a design somebody got to work then made the effort to publish it that would be an excellent starting point for youw own antenna.

I'd been wondering how to decide when the law of diminishing returns kicks in and stop laying radials.

I don't have an RF ammeter and I wondered if something as simple as observing a bulb with a (say) 5m wire laid out would offer some idea on whether a radial laid in a particular direction would be beneficial? If the bulb was bright then replacing that with a permanent radial would presumably be worthwhile. Repeat process until only a dim glow wherever it's laid. Picking the correct size bulb may be tricky especially if wanting to avoid excessive QRM from the exercise. Maybe a LED? Maybe just a diode capacitor and multimeter? Then of course the decision on how many bands to try - all? just highest and lowest used?

I'll add a quick question on radials to this too. I have a wire fence (mostly hidden by hedge) round 3/4 of the property so I ran a few long radials and soldered them to that. Would that bring any benefit over and above just the radial? The extra effort was small so I just did it.
   

That antenna is hundreds of times higher than - http://users.erols.com/k3mt/graswire/graswire.htm so of course it worked

It looks like a case of needs must - with a choice between a poor antenna and no antenna what would most choose?

I'm surprised it wasn't set up as a horizonal loop around the top of the building though. maybe there was a reason that isn't explained on the page - proximity to internal power cables maybe.

Another short multiband vertical to add to the list are the SandPiper V and MV range. These are made in Wales and probably not marketed worldwide so you'd need to arrange shipping by phone with the manufacturer.

Very little info about them on the website other than heights. There are reviews of the MV on ehamnet with one V review amongst them.

The design appears to be a bottom section resonant on highest frequency with coils and whips from the top of that for each extra band - one vertical the rest arranged horizontally.

Reviews - http://www.eham.net/reviews/detail/1439
Website - http://www.sandpiperaerials.co.uk/