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G4EAT - SK
g4bao
I'm sad to report the sudden death of John Wood, G4EAT recently at the
age of 59. John G4BAO John was a very well known microwaver and it would probably be easier to list the awards and records he hadn't won rather than those he had. I'm hoping that the UK Microwave group can come up with a fitting long - term tribute to John, and we will be discussing that in Committee in due course. If anyone has any memories of John they wish to share, please post them here and send them to me for RadCom and Martin for Scatterpoint to scatterpoint@..." There will be a family funeral on Monday the 9th of March. 73
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Re: Circular Multipole Connector
Chris - You need to be careful with those. There are several keyway configuration in use, I met this at work once, and the pragmatic solution used after we failed to identify the right connector type was to take a file to a plug an remove the keywyas that were in the wrong place. So a plug / socket combination with the same pin layout but different keyways would then mate. Of course, one simple solution would be to solder 6 wires to the pins on the relay and take them to a connector of choice. Then fill up the soldered socket with silicone to waterproof it. 'jnt A
On 2 March 2015 at 13:19, Christopher Bartram cbartram@... [ukmicrowaves] <ukmicrowaves@...> wrote:
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Circular Multipole Connector
Christopher Bartram <cbartram@...>
I'm currently beginning the process of rebuilding my 10GHz EME PA/preamp box. As part of a move to an all-waveguide antenna feed/chageover system. I have a Sivers Lab WG relay which has the control voltage and positional feedback i/o brought out via a military/industrial circular connector. To mate with this, I believe I need a six way, 6S type bayonet fitting free plug with socket contacts. Does anyone, who would be prepared to sell me it, have one of these sitting in a junk box? The price of one new is astronomical and then some!
Please contact me at <gw4dgu(at)chris-bartram.co.uk> if you can help, as I'd like to check that the dimensions are correct. Vy 73 Chris GW4DGU
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1GHz Oscilloscope
Graham - G4FSG
I have been asked if I can find a good home for a Teledyne LeCroy LC574A Oscilloscope. This is a digital, 1GHz, 4GigaSamples/s, 4channel device so very high spec.
If you are interested then please contact me OFF REFLECTOR at graham.murchie (at) btinternet.com . A contribution to the Bawdsey Radar Trust is what is being requested – see http://www.bawdseyradar.org.uk/ . The Trust is looking to raise £300k in matching funding for the potential £1.4m funding from the Heritage Lottery Fund to save the site where Radar was developed and first activated. In view of the spec of the scope then a ‘sensible’ donation would be appropriate.
Collection from Suffolk is preferred but other options can be discussed. Please contact me if interested.
Regards
Graham G4FSG
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NEO-6M
geoffrey pike
I think there was a mention at the end of last year about these GPS modules. I just was going to confirm my NEO-6M timing output is running at 10 KHz As this is what i wanted i didn't check to see if it went higher i certainly had "fun" with the cursor jumping all over the place at times when setting the configuration regards Geoff GI0GDP
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GM3WOJ 10 G beacon streaming audio back on
Brian Flynn GM8BJF
The streaming audio of GM3WOJ's personal 10 GHz beacon on 10,368.400 MHz is
back on . The Rx has moved a short distance across Edinburgh to a better
location. The path is 215 km across the Grampians. It is located at
GM8PKL's QTH which is LoS to Cain Toul which can be seen on a very clear day
from there. Signal makes a useful rain radar! It is loud at present. 20 db out of the noise on Spectran.
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Items for sale
Lars Sjöberg <sm2gcr@...>
I have a Rubidium oscillator for Sale
EFRATOM Rubidium Frequency Standard Cage code 55761 Model LPRO-101 Pn 102500-001 Ser No 43919 Price 170€ + shipping costs I also have dummy load Kathrein 1694679 (132v49 129c23) 3 x 150w 50 ohm Dc-2GHz with cooling fan. 3 Semirigid cables with Sma connectors Price 160€ + Shipping DB6NT 23cm transverter Price 160€ + shipping I have a paypal account: larzs.sjoberg@gmail.com de SM2GCR Lars ••••••••••••••••••••••••••••••••••••••••••• Lars Sjöberg Skolgatan 65C SE-91441 Rundvik Sweden email: larzs.sjoberg@gmail.com email: sm2gcr@gmail.com Phone +4673-8373236
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Re: G4JNT GPSDO LCD problem
adam9a4qv@...
Hello Andy,
thanks a lot for the quick answer. I have no problems with the date, what I need is the correct timing, and 10Mhz at the end. So this info is more than I needed, maybe I will talk to my Jupiter via RS-232 to correct this issue as G3RUH explained. Regarding the speed issue, I think I have compiled the latest version 2010 but not sure. WIll check that and do it again to verify the problem. thanks Adam
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Measuring High Power
usuallyqrt@...
I have not really been following this power measurement business closely so apologies if I am repeating others suggestions. In the days when I was thirsty for power and had only a modest through load I took a length of mediocre coax feeder adequate for the frequency knowing roughly what the loss was from its type and knowing the dbs difference between what I could measure and what I wanted to measure. Using the basic transverter the coax loss was measured at a level I could manage then the cable was put in series with the high power amp as a high power attenuator. Possibly not a good idea to have the coax rolled up if testing for any period of time. For VSWR measurement into a low power coupler you will need to take the attenuator loss into account, twice ? Maybe this lower cost method is a bit to simple to be highly accurate and is certainly not very fancy. A warm length of feeder may also give satisfaction. 73s John G8ACE
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Re: G4JNT GPSDO LCD problem
AH - Its happened. You don't say which GPS module you are using, but I bet its a Rockwell Jupiter Can I refer you to an email I received from Jim Miller G3RUH relating to the GPS modules he uses in his GPSDO. Text is copied below. Its because those modules are so old, they're rolled over and only appear to use a modulo 2^10 week count If you subtract 1024 weeks from today's date (28 Feb) you get 15 July 1995 . As for SOG readings, This has arisen before, but I can't remember what it was . I may have updated the PIC firmware on my website. http://www.g4jnt.com/GPLOCDIS.ZIP There's a later version of the firmware in there, dated 2010 but I can't remember the differences Andy G4JNT --------------------------------- From G3RUH : I need to flag up a problem with the Jupiter GPS engine in respect of its display of the date. I pass this on to you as you may be using the date information in beacon applications. As of 2015 Feb 15 [Sun], upon power-on and then acquiring satellite lock, the displayed date shows exactly 1024 weeks prior to the true date. (After nearly 20 years of otherwise perfect operation). If the unit has not been powered off, then the (correct) Date is maintained. This issue does not affect the Time, which remains always correct. In all other respects; almanac, acquisition, lock, 1PPS, 10 kHz, data streams NMEA or binary; everything is completely normal. DSP engines work in GPS week number; the "date" is a presentation layer thing for humans. If the Jupiter's date output is important to you, then you must initialise the date yourself, as follows. With the GPS receiver RS-232 stream in NMEA mode, send the command string: $PRWIINIT,A,,,,,,,,,,,,000000,ddmmyy[CR][LF] with the appropriate date. Example; for 2015 Dec 31 you would send: $PRWIINIT,A,,,,,,,,,,,,000000,311215[CR][LF] Note: this is 36 ASCII bytes plus 2 terminating bytes CR LF, (hexadecimal 0x0D 0x0A), making a total of 38 bytes. The CR+LF are essential, and must be in that order. There are 14 ","s in the string. There is no tolerance for error in this byte sequence. For example, your dumb terminal software must not add any characters to the end of the sequence. A file, init_date.txt that contains this command can be found in http://www.jrmiller.demon.co.uk/projects/ministd/jupcom.zip Another option is to implement back-up of the RTC and SRAM, which is a 3V to 5V signal applied to pin 3 of the 20 way connector. The drain is about 50 µA. The voltage can usefully be from a NiCd/NiMH/Li rechargeable battery, or even 3x AAA Duracell. Once correctly initialised, the date should remain correct indefinitely. Hope useful. 73 de James G3RUH
On 28 February 2015 at 16:08, adam9a4qv@... [ukmicrowaves] <ukmicrowaves@...> wrote:
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First UK Microwave Group Low Band Contest 2015, 8th March - Activity list
John Quarmby
The first UKuG contest of 2015 takes place next Sunday 8th March, from 10:00 to 16:00 GMT, on the 1,3, 2.3 and 3.4GHz bands.
Full rules are here: http://www.microwavers.org/files/2015-mwrules_v4.pdf The online log entry system is here: http://microwave.rsgbcc.org/cgi-bin/readcal.pl As usual I will put together an activity list, please let me know your plans in the format below: Callsign: G3XDY Locator: JO02OB Bands: 1.3GHz 400W, 4x23ele 2.3GHz 100W, 0.8m dish 3.4GHz 20W, 0.6m dish Talkback: Direct calls on 1.3GHz plus ON4KST Times: Throughout If you can get details to me by the end of Friday 6th March please, I will publish the list on Saturday 7th. 73 John G3XDY
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Re: Help spec on relay
John Quarmby
And the relay is spec'd for operation to 18GHz.
On 28/02/2015 13:16, Geoff Blake
geoff@... [ukmicrowaves] wrote:
Hi folk,
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Re: Help spec on relay
John Quarmby
Hi Geoff
The NSN you quote actually looks like an Amphenol part number. The nearest I can find in my old Amphenol catalogue is 303-10179-2, which is a 12V SMA c/o relay. Specs at 10GHz are VSWR 1.4 max, isolation 70dB min, insertion loss 0.4dB max, RF power 35W CW max. Coil resistance is 65 ohms for 12V DC operation. Sounds like it should fit the bill. 73 John G3XDY On 28/02/2015 13:16, Geoff Blake
geoff@... [ukmicrowaves] wrote:
Hi folk,
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G4JNT GPSDO LCD problem
adam9a4qv@...
Hello guys,
I am running the G4JNT GPSDO 2x16 LCD 16f628 fw on my system and noticed that the date is wrong. Last year the date was ok, but not this year. Today, I have displayed the July 15. The time is ok as well the position and the locator. Since begining I noticed also wrong speed over ground indicating 161mph and 072.0m/s even I am not mowing and using my 10mhz reference at home for the lab instruments only. Any idea? Thanks Adam
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Re: Help spec on relay
Geoff Blake <geoff@...>
Hi Steve, Long time no speak. Thanks for the info. Of course, I should have recognised the lack of NSN format, but it is years since I worked with them :-) Oh well, I will have to use the 28V inverter and relay then. The relay itself will probably do for the next project, 23cm portable transverter. 73 Geoff ################################################# Geoff Blake, G8GNZ JO01fq: Chelmsford, Essex, UK <geoff@...> or <melecerties@...> Using Linux: Ubuntu 14.04 on Intel or Debian on UltraSparc and Apple OS X 10.10 Yosemite on my Macbook Pro. Avoiding Micro$oft like the plague. #################################################
On 28 February 2015 at 13:43, Steve - Home Steve-Krull@... [ukmicrowaves] <ukmicrowaves@...> wrote:
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Re: Help spec on relay
Steve - WB0DBS
Hi Geoff, The NSN seems to be missing a few digits. The standard number is 13 digits in a 4-2-3-4 sequence. Agilent/Keysight shows it as obsolete, 2GHz, SMA but that's all the information they provide. HTH, Steve WB0DBS
On Feb 28, 2015, at 1:16 PM, Geoff Blake geoff@... [ukmicrowaves] <ukmicrowaves@...> wrote:
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Re: Power meter for 23 cms over 300 watts
Graham G3TCT
Another option I'm using is the Xeropage power meter which runs from a USB laptop connection and is good value -
http://xeropage.co.uk/powermeter.html I'm using this in conjunction with a Narda 20dB directional coupler (from ebay) and some SMA attenuators to give a variety of sensitivities from -40dBm to +60dbm (in theory - I can't test it at that level though!) A good coupler allows you to get an indication of return loss as well. I started off with a Boonton 42B which worked very nicely for a year or so until the diodes in the head gave up. This was disappoining as I never put excessive power into the head, and I suspect it died either through static discharge or old age. So I now have a useless Boonton to dispose of, unless anyone has a way of repairing the head. I tried substituting a SMD microwave diode but the sensitivity and linearity are hopeless. 73 Graham
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Help spec on relay
Geoff Blake <geoff@...>
Hi folk,
Can anybody help with the spec. of a relay please? It is the usual SMA change over type, the only unusual point is that it is 12V. The manufacturer is Joslyn Defence Industries and the N.S.N. Is 303-10179-10. It is also a HP 3106-0024 and Joslyn seems to be an alternative supplier to Amphenol. I would like to find the max frequency and isolation at 10368MHz please. Thanks Geoff -- ################################################# Geoff Blake, G8GNZ JO01fq: Chelmsford, Essex, UK <geoff@...> or <melecerties@...> Using Linux: Ubuntu 14.04 on Intel or Debian on UltraSparc and Apple OS X 10.10 Yosemite on my Macbook Pro. Avoiding Micro$oft like the plague. #################################################
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Re: Power meter for 23 cms over 300 watts
Eddie G0EHV
Hello,
Yes fully agree re UK Microwave Group membership, a bargain!
I have several couplers, home brew and others of a dubious source
(EPay).
They have all be measured and calibrated for me at the excellent microwave
round table events at either Finningley or Burntisland.
The associated microwave detector diodes also came from Ebay and again were
calibrated at the RTs.
My “super duper”coupler was bought at the GM RT for a very reasonable sum
and came with individual calibration info for each band from 50 – 2320
MHz.
It weighs about a Kg so I assume “highish” power.
I’ve also a couple of Bird meters with some useful slugs, but as already
mentioned – for indication only!
Regards,
Eddie
G0EHV
From: mailto:ukmicrowaves@...
Sent: Friday, February 27, 2015 2:30 PM
To: ukmicrowaves@...
Subject: Re: [ukmicrowaves] Power meter for 23 cms over 300
watts Hello Tim
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Re: Power meter for 23 cms over 300 watts
Christopher Bartram <cbartram@...>
Hello Tim
Just in case anyone needs this done but in my lab at the office I have the capability of measuring coupling factors, loss and directivity of Directional couplers, certainly up to 23, probably up to 10GHz. Don't all rush...Before John, G4BAO writes something similar ( :-) ) it's worth reminding people that members of the UK Microwave Group ( <www.microwavers.org> £6/year) have free access to a technical assistance network. Most of us providing that service have the ability to make meaningful measurements of things like directional couplers to frequencies well up into the microwave spectrum. Vy 73 Chris GW4DGU
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