AmateurRadio.com

I got this red LED flashlight as a Christmas present. But unfortunately the intensity was way too high for what I intended to use it for. A soft red light preserves your night vision, and is ideal for use with a telescope in the dark as was my intention. But if the intensity was as high as before the modification, night vision would suffer.

I then found this YouTube video describing how the controller circuit board could be replaced by one with more functions. As recommended I therefore ordered an AMC7135*8 2800mA 4-Group 5-Mode Circuit Board with 8 AMC7135 current regulators in parallel. The image shows the the original circuit board as connected before the modification in the front in the image and the new one behind it.

The new board gave me the choice of one of 4-groups:

1. 3-mode: Lo (5%) – Hi (100%) – Strobe
2. 3-mode: Lo (5%) – Mid (30%) – Hi (100%)
3. 2-mode: Lo (10%) – Hi (100%)
4. 5-mode: Lo (5%) – Mid (30%) – Hi (100%) – Strobe – SOS

Sverre Holm, LA3ZA, is a regular contributor to AmateurRadio.com and writes from Norway. Contact him at [email protected].

I'm the chap who looks after our monthly Co-ordinated Listening Events (CLEs).

About 70 of our NDB List members have taken part in recent CLEs - and the other 550 members haven't. Only about 250 members have ever sent a CLE log (including all ex-members), so more than 300 current members haven't.

If you are one of the 300+, do you sometimes look at our monthly CLE results and maybe find bits of them interesting or useful?

This is NOT a sales pitch to try and make you take part, welcome though that would be! However, if several 'non-CLE' Members are finding the results helpful, I would like to know whether we might improve the way the results are presented to make them more understandable and more useful to our members generally?

If you are interested, it would help me if you could please reply DIRECT TO ME at [email protected]



I will keep your reply confidential and I will try to acknowledge all replies individually - there may be just yours or there might be 100 of them !!


1. How often have you found any individual listener's CLE log of interest?


2. How often have you looked at any of the CLE combined results?

Once or twice
Sometimes
Often

3. (if any) Which results were of interest?

Tables, etc. in the Excel attachments
Tables, etc. in the CLE Archives


4. Did you find that the results needed further explanation?

Yes, sometimes
Yes, often
Yes, always






6. Have you sent your own listening log(s) to NDB List?


7. Finally, please confirm that you are one of the 300+

I've only sent 1 or 2 CLE logs




Brian Keyte

(CLE Co-ordinator)






Steve McDonald, VE7SL, is a regular contributor to AmateurRadio.com and writes from British Columbia, Canada. Contact him at [email protected].

I have posted twice (1st one and the 2nd one) regarding CQ magazine and trying to contact them. I have called and left  messages, then called and talked to someone who forwarded my call to voice mail and again I left a message again and also I have emailed them. To date I have had no call backs from my messages or have I received an email regarding my issue! BUT I have received 2 emails from them wanting to know if I would like to purchase a calender for 2015!!! So they do know my email and it seems there emailing bot is up to date with sending out advertising to it's customers. When my subscription runs out I am done with CQ! 
Mike Weir, VE9KK, is a regular contributor to AmateurRadio.com and writes from New Brunswick, Canada. Contact him at [email protected].

The troublesome TR9500 has developed another fault, well it has likely had this fault since I've owned it but I have only just spotted it.

After making repairs to the microphone amplifier and the receiver pre-amplifier the rig seemed to be working fine, I'd even used it several times during the UKAC contests with some success.

The 70cm band is under used locally and activity seems largely restricted to repeaters. Due to it's vintage the TR9500 doesn't have CTCSS tones and so cannot be used to access repeaters without some modification and I've been looking at adding a CTCSS board.

In the meantime I really wanted to use the TR9500 a bit more and was hoping to make it part of a satellite station, the TR9500 acting as the UHF uplink transmitter (LSB) and the VHF 2m TR9000 as the downlink receiver (USB) for the AO73 (FUNCube-1) and other satellites.

The satellite portion of the band plan is at 435-438MHz and it was when setting this up I discovered the TR9500 neither received or transmitted in the upper part of the 70cm band (435-440MHz) below this everything was hunky-dory.


It hasn't taken long to locate the issue, the HET unit employs two crystals L33 (36.6222MHz), L34 (37.1777MHz) which are switched in to the oscillator Q1 depending on the selected frequency. L33 being referred to as low band, L34 as high band the switching occurring around 435MHz.


The switching HL signal (via R10) and transistors Q3/Q4 are working correctly it is just crystal L34 is not resonating. The surrounding diodes, capacitors, inductors and resistors all look fine, no obvious shorts or broken joints.

I have to do some more diagnostics to rule out any of the passive components but if it is the case that the crystal has failed then it may prove difficult to source an economical replacement.
Andrew Garratt, MØNRD, is a regular contributor to AmateurRadio.com and writes from East Midlands, England. Contact him at [email protected].

With my KX3 on the fritz (boxed up, ships out tomorrow) I won’t be able to join in on the fun in chasing K1N on Navassa Island. But I did manage to sneak in some time this evening on K2SDR’s internet enabled software defined radio station. Just listening to the CW pileup makes you wonder if you’ll ever be good enough to pick them out of the pile! Here’s a view of what 20M CW is like….K1N is the station on the left…the rest to the right are in the pile!

Michael Brown, KG9DW, is a regular contributor to AmateurRadio.com and writes from Illinois, USA. Contact him at [email protected].

This evening I listened for G6ALB on 70cm. Andrew is 3km from me. We both have V2000 vertical co-linear antennas. He was using a very low cost SAW locked TX module, which produced as much FM as AM when modulated with an electret mic. The biggest problem was Andrew’s low power and low level of modulation.  He needs more mic gain, more TX power (10dB more?) and some pre-emphasis on the audio. TX power today was very low milliwatts. From 433.925MHz up to at least 433.990MHz a lot of squeaks and whistles could be heard, presumably from more local ISM devices. I was receiving G6ALB using an FT817 at about RS41 on FM and weaker on AM. This very initial test produced results that were expected. To use a super-regen module on RX (the intention is a very simple AM voice transceiver) will require G6ALB to be considerably stronger than on these first tests.

Roger Lapthorn, G3XBM, is a regular contributor to AmateurRadio.com and writes from Cambridge, England.

I was excited to see the Raspberry Pi 2 announced today

One is on the way. It will be interesting to see how it works out – particularly for some of the more heavy duty apps I have tried in the past such as FLDigi.

A new version of the OS compiled for the new processor is required and can be downloaded here

More news when it arrives!

Tim Kirby, G4VXE, is a regular contributor to AmateurRadio.com and writes from Oxfordshire, England. Contact him at [email protected].