Should contest rules allow and act upon 599K QRM reports?

Saturday, 28 February 2009

Small Wonder Labs SW40+ and embedded K1EL K-PCB (K12) keyer

Small Wonder Labs website:
and K1EL Systems
are two of my most visited websites for QRP gear and ham gadgets. In the past I bought 2 of the SW+ series QRP rigs (80 & 40m) and was and still am really pleased with their performance.

I really missed a keyer though and bought an external K12 keyer from K1EL to use with both rigs. This worked fine, but the whole point of these small rigs is their simplicity and portability. So to keep things simple, I decided to buy the same keyer chip (K12) but in K-PCB format which was small enough to mount inside the transceiver case.

The K-PCB kit takes around half an hour to build and the same again to mount inside the SW+ rig (it's so light I just used cable ties). The kit is $10 which is unbelieveable value for what you get and it fits easily inside the SW+. Unfortunately my kit was missing a 1000pF cap which I replaced from the junk box and the 2N2222 NPN transistor (used to switch gnd to the keying line of the SW+) had to be replaced.

The only slight question was how to get the sidetone into the audio chain of the rig? The K-PCB has a low level AF output for this purpose and after some experimenting I found that the best place to connect it to was the top of resistor R10 (vertically mounted) on the SW+ pcb. That done, I could hear CW commands from the keyer chip through the RX audio of the SW+.

Have a look at the above websites for details on the two kits they really are worth every penny.

Thursday, 5 February 2009

IOTA 2009. Shared serial number pool with Wintest

MM3T will be multi-op for the first time with myself and Simon M0GBK taking up the challenge for IOTA 09. We're off to the isle of Skye this time, but will still be EU-8 for the benifit of SCP files out there. We will have 2 stations operational for 24 hrs and will be operating all bands on both SSB and CW.

One station will be on mults only and the other station running for an hour, then we'll swap over. We will be using Wintest contest logging software, which can keep track of each stns contacts (RSGB requirement) and contribute both to one log (duplicated on both computers for safety). This means the stations will aquire sequential serial numbers from the same pool. The laptops will be linked via a router and if a mobile signal is possible, the cluster will be shared across the network.

The sharing of a serial number pool from Wintest presents some problems. It is possible for both stations to log the same serial number (if enter is hit on both laptops at the same time). It's also possible for the serial number to increment just before you hit enter (due to the other station finishing a contact before you). To avoid this contention for serial numbers, an operating procedure must be in place. I have found it is best to put the onus on the mult station to avoid contention as this station normally has more time to think about it:

Mult Station Operating Procedure:
Wait till the running station has just completed a contact. Dupe it while he is calling CQ, thus reserving the next serial number. This should be done quickly before the running station requires the next serial number. The cursor is then moved onto the dupe ready to edit it with the next station worked. In this way, serial numbers given out never need changed at the last minute and are guaranteed to be unique.