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  • New LZ1AQ commercial amp and dual loop antennas.

    To save starting a new thread this is my current, if somewhat ugly method for connecting loops to a LZ1AQ amp.
    I started out with intention to use a clear top junction box

    but while considering dissimilar metal corrosion I remembered I'd also ordered a larger enclosure that may keep most electrical connections inside, I decided to temporarily use that while I working out the external connector layout for the original box (dependent or orientation and ease of inspection/rework).

    The element wiring exits out the back of the box through four M6 machine screws and lugs driven by the enclosure layout (same as the original box in one dimension, shorter in the vertical) I have two 6mm nylon plates behind that, the idea was to have a test base I could swap out elements without too much risk to the PCB, I also wanted the bike rims to be self supporting if I have it horizontal.

    I do still want to work on the clear top enclosure as it is neater but this should hopefully survive the winter and I can swap the current rims out for something larger.

    I used a 4mm banana plug socket for the drain wire and an overly expensive (Bulgin?) waterproof RJ45 housing from the work junk pile, I've since found more reasonable RJ45 connectors on Ebay/Amazon.
    I'll put another spade crimp socket on the CAT5 connector shield so I have the choice to earth through the shield or separate wire.

    Right now it is screwed to the fence, I had to think about that, ended up with the nuts on the back so I remove the back nylon plate screw that to the fence then bolt the box+rims to that, not very good solution as things flex while the back plate is off and kept the holes close to bolt size, but this is just a way to test mechanical ideas and get back into CAD (Sketchup for now) which I used to quite enjoy.

  • Power line noise.

    Thanks for your visit but I have had the issue addressed by higher powers.
    Storming service levels.
  • Radio over Fiber Optic

    Something I see as a potential market - more modular radio kit.
    For example RX front end with optical standard IP network connection back to the rig, or for QRP systems complete "QRP rig in a can" (mast mounted), with optical interface back to the shack.
    I know I'd still need DC at the antenna end but where anyone has only 5W to play with having it right at the antenna feed point (even elevated) would make the most of it.
    Where to feed the optical cable? feed it along your radiating wire if need be.

    Here being bathed in QRM and the limit of my "get it away from the house" at about 30ft (9m) I see every bit of copper as a potential way to inject noise back in. If I had a QRP radio that was waterproof and mast mounted I could concentrate on shielding the DC as main potential pickup, hell with a tube of 18650 batteries I could probably run it physically disconnected from DC feed for hours (or battery for RX, DC for TX).

    I have bought enclosures and network kit with this in mind, I just need the IP based QRP rig that I can loft in a box at the extreme (lol) end of my garden. perhaps some small solar cells to top it up during the day.
  • crashes

    I have noticed my WSPR running the old script (yes I'm too lazy to update it right now) is seeing different connection times, seems something is kicking the individual recorder sessions?
    When it happened before (to best recollection) it would have been an all-or-nothing when I restarted something in the network link.
  • Fibre Network (basic knuckle-dragger level)

    (September 2018)

    Fibre used to be expensive and (IMO) gave the impression it was not for home use, things have changed.

    For example, if I want to connect a few (4) items across 20m at 1G, keeping the items separate by VLAN's, I'd need at a minimum two five port managed networks switches and 20m CAT6 (or 5E).
    If I pick some basic units that will probably come to about £100 including tax.

    If I want to link the same number by a fibre (1G) 20m it is a few pounds more.
    For example:
    Six port managed network switch (five copper one SFP port) about £34 (x2) Mikrotic RB260GS (CSS106-5G-1S) (
    two Gig SFP modules UBIQUITI UF-MM-1G SFP Module, 2pack (pair) £16.50 (
    OM4 LC to LC Fibre Optic Cable 50/125 (Amazon) (20m) £19
    All in (forgetting postage) £103.5

    If you get modules from they are about £6 each, if I drop to OM3 20m cable (not future proofed for 10G) that saves another £9, suddenly copper looks expensive.

    If I want to increase the link speed to 10G and number of items directly connected at both ends to twenty it's about £280.
    £110 each for the 24port switches with SFP+ ports (MIKROTIK Cloud Smart Switch CSS326-24G-2S+RM) and about £15 per SFP-10G module ( +the OM4 20m cable above.

    As the SFP modules are bought separately you could connect these items by 200m or 2km of fibre just selecting the SFP transceivers and fibre cable to suit.
    I've only used multi mode transceivers as my links are local (less than 300m).

    As I said real basic info this no optical patch leads, most basic modes no self termination of fibre. I also went with one router for bridging copper WAN into a fibre setup (MIKROTIK Cloud Router Switch CRS106-1C-5S ( -£45) and one external router for mast mounting, not used yet as I haven't worked out where I want it (CRS105-5S-FB) on offer ( at £53 currently with one SFP-Copper transceiver.

    What I have learnt from this short test in my (dusty) house?
    This is mainly paranoia but it came to mind while digging out holes. Plan any fibre route (completely) and don't get the cable out until you are ready, cover the ends in transparent packing tape (just over and back on itself) so that the ends are dust free after installation when you take the covers off. Likewise don't remove the covers from the transceivers until you are ready to connect, have more than enough fibre cable on any link, in these uses it is virtually loss free so if you have a 15m excess ready for the next use it will make zero odds, much better to avoid tight bends with short cable. Find a route where the cable won't get crushed, I ran mine in the loft. I had zero problems with dirty fibres but it pays to avoid dust rather than add the price of cleaning kit if you are only making changes infrequently.
  • FM (88-108) Interference

    Ha wasn't expecting that! at least the cause was found to be external and actually fixed.
  • Any Ideas [AM BCB overload]

    Search "Spiderbeam 12m Fiberglass", that is designed for hoisting light antennas but a "10m fishing/flag" pole minus the two top sections will get it up a fair way and cost a lot less for a test setup.