Sunday, 30 July 2017

Tool Box

Here a few things which I've been using for years, I must have had them all for over 10 years now.

Tool Box - probably a Christmas present, like most of the stuff here. I don't think I've ever completely emptied it since new.

Connectors Box - this is where I keep any adaptors, other connectors, memory cards etc. Spot the AT to PS/2 keyboard adaptors which even I've got to admit are just wasting space in there but have I ever emptied this since I got it in about 2002? Probably not. From Woolworths, so that dates it a bit.

 6-way Screwdriver. Stanley 68-012. Until today, I hadn't realised it was 6-way. The shaft of the screwdriver will fit two different sizes of nut. Good enough for nearly anything you would normally use a screwdriver for, except small terminals or anything where there might be live connections nearby. Apparently the new model is worse, so this may be becoming something of a classic.

Charger - Vanson Speedy Box. It's not the fastest charger but I got it from Maplin at the time when the higher capacity Ni-MH cells (1800mAh+ for AAs) were quite a new thing. It also discharges cells.

Laptop Bag - By Kensington, from Ebuyer when I got my first laptop in 2005 (and used for another 4 after that). It's a backpack but the straps can be hidden away and can be turned into an over the shoulder bag (but I think I've lost the strap for that without ever trying it).
With 16:9 displays, the basic 15" screen laptop has got wider and you can see mine hardly fits in the bag now (it was bought for a 15" 4:3 ratio screen model). That's a 640GB Toshiba USB HDD in the bag.

Thursday, 13 July 2017

Bit Of A Lift

On the way home from work I was stuck waiting for a train an hour so had a play around with the Netmonitor app on my phone. I was in an area where there is, normally a 2G phone signal if you're lucky. This means that if there is any odd propagation at UHF, all sorts of different phone masts start being picked up, and being near the sea also helps.Well after leaving Netmonitor on for a bit, it had picked up a few cells in the Stranraer area, which is over the horizon so pretty good, but the best was a GSM signal from Larne in Northern Ireland (around 160km), and a 4G signal from Donaghadee, almost as far away across the Irish Sea.

When I got home, there were some big signals on the 70cm band, with at least one of the two Isle Of Man repeaters on 430.825 being full scale. I had a go at using the DMR handheld indoors to access GB7BR at Bride, and managed to get in. Also got into GB7UL at Carrickfergus from the handheld indoors.

 This repeater on 430.825 is usually no S-points, but full scale here.

A handy 'beacon' on 427.850 - Dublin buses trunking data, active 24/7 and the first thing to come through when there is any propagation across the Irish Sea on UHF.

On 145MHz simplex I spoke to GI0BDX in Newtownabbey.

One signal which I'm still not sure about is an Echolink gateway on 439.100, which I can't find on any lists (unless it's in Germany, which seems unlikely). Could be in Ireland as that's where lots of other signals were coming from.
Today (Thursday) everything was back to normal, back at its usual signal strength.

Thursday, 6 July 2017

The Perfect Radio

Here's a list of features I'd been thinking of for the perfect radio - mostly for VHF/UHF use and it would also be used in scanner mode quite a lot so many are scanning related. It's just a list I made for myself on my phone so not too much detail.

Radio Features:

Save to SD card/PC in format which can be exported as a video showing s-meter, freq etc. Only record when squelch open.

App to play back recordings with audio.

Smart skip - channels which are too busy get locked out until a break in activity - e.g. if >30% of scan passes are active it gets locked out until drops to <20 br="">
Per-channel delay times - e.g. wait 60 seconds even if squelch closed on a calling frequency in case they call again.

S-meter squelch on per-channel basis

Reset of all lockouts

Lockouts can have an expiry time

Linked search bands (like UBC3500)

Lock out ranges of frequencies or modes (applies to memories in that range too).

Record stats on channel use - auto lock out channels which are never used.

Open squelch on ANY CTCSS tone.

Lock out all non-tone channels

Signal in dBm on display

Select a lockout mask from a list

Change settings by geographic location - new set of memories or lockout mask when leaving town.

Select radio profiles from a list.

DMR auto identifies cc, slot and tg.

Direct entry of talkgroup via keypad on DMR.

Import DMR contact list of any size from csv file.

Export of all radio activity to CSV file (time and location of any signal above a threshold or transmission).

Audio AGC receiving on FM and digital modes - can be applied to recordings.

Each channel member of a rule group, with tones, lockout, power, geo zones etc.

Zones - distance from a point, grid squares etc. Can be either allow or lockout.

Priority tx frequency - when radio is set to auto/scan mode, any ptt activity transmits on a fixed calling frequency (could be APRS/emergency). If PTT pressed for >2 seconds, receive goes to that frequency and scanning stops. If not, it carries on scanning or rx on other freq.

Built in usb audio and serial port.

CAT control even on handhelds (micro USB) and FM mobiles.

Access over telnet/SSH, or serial console with command line.

Web browser access on ethernet/wifi models.

Bluetooth earphone/mic support.

Music playback off sd card/aux in, through bluetooth or speaker. Mix music with receive audio, ducking with squelch. So rx audio can go through car speakers.

Soft sub band muting, when sub band rx broadcast FM etc.

Channels can be scan groups or search bands.

Tone/dmr only smart search saves any real channels and not interference. Can choose to save only correct tone/group or ANY tone/group on that freq.

Tone/dmr only scan can still pause silently on other found channels for 5 sec if busy and show MPT1327 trunking ID etc. Channels can be set to stop while busy but have speaker audio muted, either recording or not recording.

Lockout rule for channels by time and date.

Programmable sequences of vfo/scanning e.g.

Vfo 145.500

If no activity for 10 min or if squelch open 30 sec in 60 sec step on

Vfo 433.500

If no activity for 10 min step on else goto start

Scan all groups

Goto start.

Email alert on events (per channel etc.)

Override of tone squelch above signal threshold

Voice keyer uses mp3/wav files

Schedule playing file/morse ID/beep/dead carrier, with delay on busy channel.

Built in decoding of jt65/psk/cw/packet/wspr with upload of spots or saving to text file. Aprs gateway support (passcode etc.).

App for android with ptt button support to simulate radio over internet connection.

Parrot mode - records up to a time limit and transmits received audio. Can use audio agc. Minimum tx time can be set or a preset audio file can be played instead of received audio if squelch was open for less than minimum time (broken signal or testing access).

Programmble i/o (3-16v in, 5v , source, sink or dry relay contacts out?) For events, ptt, squelch out etc. External squelch contacts can be different to audio squelch.

Digital vox on any signal above digital silence.

Momentary ptt latch/unlatching signal

Tx deviation independent of rx bandwidth

If signal above threshold, squelch changes to s-meter.

Direct link between 2 radios over network - controls on one radio take over from the one with the antenna, with full tx/rx audio.

Analogue i/o programmable, 0-10v in, 0-5v out for external s-meter, power control. Events can set or be triggered by voltage levels.

SWR available on analogue output or to set digital i/o.

Parameters of other radios can be read/written over network/internet. E.g your frequency can be sent to server/friend if within certain bands so they can see if anybody is on a certain band. Events can be sent, ptt pressed, squelch open etc.

Rewind last 20 seconds of audio - when squelch was open.

Events can be triggered by a certain frequency being active or above a threshold - "i can hear 440.800 so change to midlands profile" or "if paging >-30dbm, lock out range 108 - 200 MHz", checking on a 'silent' scanning memory.

Replace audio with a few seconds 'ringtone' or silence on selected channels when squelch opens, or if squelch opens and no tone/encrypted/no audio.

Squelch open/close 'roger' beep can vary depending on signal level.

Receive diversity on 2nd antenna.

Dual receive relay scan - sub rx scans and tunes main rx to active freq. Stays on that freq until something else found.