Re: [Elecraft] spurious signals problem solved
On Fri, 2007-02-09 at 13:43 -0700, Terry Wilkinson wrote: Hi everyone: Thanks for the replies to my post regarding spurious signals. Just discovered the problem: I have an uninterruptible power supply, so I tried plugging my K2's power supply directly into a wall plug, then unplugged the UPS, and the hash went away. Looks like my UPS got fried. Time for a new one. It's probably not fried, Line interactive UPSes can produce a of of RF Junk on the output ( input) all the time Off Line UPS es tend to be more benign since whilst AC is there they simply pass though the AC. When AC fails they run an inverter to make AC. On Line units are supplying inverted output all the time I have a couple of APC smartUPS units that are absolutely filthy and took a lot of filtering (input and output) to tame to the point where they don't totally trash HF. These are the smartUPS1000 units and are good USP units for server grade IT Equipment I also had a Smart UPS 5000 (5KVA ) UPS that no matter what I did I could not tame fully. Thankfully it's now in our Datacenter many miles away.. To Summarise. If you are looking for Radio Friendly UPS look for an Off line UPS. It probably will be noisy during a power failure but it should be fairly quite when AC is present. With Off line UPS units the main source of noise during normal operation is the Switch mode power supply that is used to charge the battery. Line filtering should take care of that if it is an issue. Older (heaver!) units used a proper linear power supply to charge the battery and are clean. You can usually pick these up cheap second hand and the only Maintenance they are likely to require is Gel cell replacement. Use good Quality Gel cells sourced locally as these will be a fraction of the price that the manufacturers charge for the same thing. 73 Brendan EI6IZ ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] spurious signals problem solved
In message [EMAIL PROTECTED], Terry Wilkinson [EMAIL PROTECTED] writes Hi everyone: Thanks for the replies to my post regarding spurious signals. Just discovered the problem: I have an uninterruptible power supply, so I tried plugging my K2's power supply directly into a wall plug, then unplugged the UPS, and the hash went away. Looks like my UPS got fried. Time for a new one. I quite enjoyed that short series of posts Terry; glad you got it sorted in the end! Many thanks :-) Trev G3ZYY -- Trevor Day Sunny Saltash ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
Re: [Elecraft] spurious signals problem solved
Terry: Better the UPS than the K2. It did its job of protecting what was plugged into it. Remember, the gel-cell inside can be removed and used as a great power supply for any of your QRP rigs. I don't think I've run my K2 on anything but gel-cells so far. If you are lucky, maybe you can also salvage the charging circuit for the battery. 73's, John AA0VE Terry Wilkinson wrote: Hi everyone: Thanks for the replies to my post regarding spurious signals. Just discovered the problem: I have an uninterruptible power supply, so I tried plugging my K2's power supply directly into a wall plug, then unplugged the UPS, and the hash went away. Looks like my UPS got fried. Time for a new one. Regards to all, Terry W1BPJ K2 #5944 ___ Elecraft mailing list Post to: Elecraft@mailman.qth.net You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
