Saturday 11 January 2020

Modified Schwegler 1MF

The Swifts Estate nest boxes in Fulbourn Cambs are one of the most successful projects in the UK: 276 nest boxes in 250 dwellings are home to 100 pairs of Swifts, together with House Sparrows, Great Tits, Starlings and House Martins.

The nest boxes comprise 168 custom made internal boxes and 54 Schwegler 1MF double boxes (108 nest chambers). However, 90% of the Swifts are in the internal boxes with only a handful in the Schwegler 1MF's. (See here for internal nest box design).

2 internal entrances near the top of the gable
and the modified Schwegler 1MF. The other side
of the gable is a mirror image (click to enlarge)
So we mulled the idea of modifying the entrances of the Schwegler 1MF's to be more like the internal boxes.

Andrew Tristram, who lives in another part of Fulbourn also had 2 Schwegler 1MF's on his gable, which attracted breeding Starlings. He reduced the entrance size and played Swift calls, but still no Swifts. We then installed 4 Cambridge System internal boxes inside the roof space, and 2 pairs of Swifts moved into them.

As an experiment we then made 2 new entrance plates for the 1MF's with horizontally facing entrances, with a similar appearance to the Cambridge System entrances.

Although it is too early to draw firm conclusions, 1 pair of Swifts moved into 1 of these modified boxes. We intend to replace more of the 1MF entrances, but we need to wait another season to get any more data, so we thought we would publish this now.

Saturday 4 January 2020

The Swift Micro Caller

Graham Fell of Kendal Swifts has discovered some amazing new technology: an MP3 player costing less than £1. 

Together, and with others, we have been trialling it and so far we believe that it is a viable, very low cost solution. There are many vendors selling this piece of kit; try googling "TF card U disk MP3 Format decoder". It comes as a printed circuit board, there is no housing, you need to supply your own.
You can plug calls in on a USB memory stick to the U disk port, or on a Micro SD card into the TF card port. The tweeter should be connected to the 3W Speaker port. The system is powered with a Micro USB cable compatible with a mobile phone or Kindle charger (not iPhone).

Our analysis so far:
1. Volume is not quite as loud as Cheng Sheng/Kinter type systems at maximum volume, but it is loud enough for most situations. Usually one turns the volume down on these other systems.
2. Sound quality is good, with no distortion at maximum volume.
3. Control buttons not as convenient as control knobs, but not difficult to use.
4. There is only one speaker port (2 on a Cheng Sheng). We have not tried connecting 2 tweeters in parallel to this port.
5. We don't know yet what the Swifts might think of it [Update: we have attracted Swifts into boxes.]
6. It seems to consume a very low amperage, so we are testing to see whether it is feasible to run for a whole season on a single battery charge, without solar panel.

For a complete system, you need:

The TF card
USB memory stick or Micro SD card with calls in MP3 format
Micro USB cable (£1 from Pound shop)
USB mains plug 
Tweeter and speaker cable

You can probably buy all this for  less than £10

And you need a 240 volt timer. We recommend a digital timer as it does not need resetting after a power outage.

As an interim we have made some housings on a laser cutter. as in the following pictures. For this illustration we have a short speaker cable, you may well need 6 metres or more:

Micro Caller with Micro SD card
Micro Caller with USB memory stick
With power on and a USB memory stick or MicroSD card inserted, the Micro caller will start to play, cycling indefinitely through all the tracks.
To increase volume: continuously depress the Next/V++ button
To decrease volume: continuously depress the Prev/V-- button
To move to the next track: short press on Next/V++ button
To move to the start of the current track: short press on Prev/V-- button
To stay on the current track: press Repeat
To revert to cycling through all tracks: power off and then power on again.