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Re: Steel box section masts
John Lemay
Noel
I think a more appropriate question is to consider whether the roof rack is strong enough. It’s likely to be made of much smaller material than 60 x 60mm and could be the weak point in your proposals.
To answer your question about size and wall thickness, an increase in bending strength is best achieved by increasing the size and using the same wall thickness. But the limitation on this is that the wall must not be so thin as to be flexible because it will fail by crushing.
60 x 60 x 3mm box steel is pretty substantial and in my opinion will serve your purpose well. If you place such a large load on the top that the pole bends, you will in any case find it very difficult to raise from the horizontal position.
What will you do at the base of the pole to keep it all upright ? It will need a restraint and just sticking it in the dirt won’t suffice.
Chris’s suggestion about a truss is useful. A lattice section is stronger for the same weight of material, but more costly unless you can find something which is second hand, or scrap from a longer section that got bent.
Hope this helps.
John G4ZTR
From: ukmicrowaves@... [mailto:ukmicrowaves@...]
Sent: Monday, November 14, 2016 13:36 To: ukmicrowaves@... Subject: [ukmicrowaves] Steel box section masts
I’m currently reworking my VHF/UHF & microwave /p system based around a Land Rover and wonder if it is practical to use standard steel box section (preferably galvanised) as a single mast section with rotator and antennas / transverter on top (using box section rather than pole gets over problems of it rotating when being raised / lowered). I’m thinking of using a 60 * 60 * 3 mm steel section about 5 metres long which would be mounted / pivoted at about 1.8 mts off the ground on the roof rack. 1.8 mts of pole would be extended beyond the roof rack when on site and used to pull up the remaining 2.8 mts to the base of the rotator above the pivot point. I am not that mechanically minded, but looking at various commercial systems it would appear that the mast would be stable enough once raised (my own tennamast has a 40*60 top section), but the big question I have is whether it would actually strong enough or would it bend with the head load during raising and lowering process. If yes, then what can I do – increase the box section size or is it better to increase the wall thickness or what? Any help / advice / alternative solutions appreciated – and where can I buy galvanised box section in 5mt lengths? 73 Noel – G8GTZ
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Re: Steel box section masts
Christopher Bartram <cbartram@...>
Hello Noel An idea which doesn't seem to have caught-on, but which I think should, is to use 'trussing': these are the lattice mast sections which are used by stage lighting and PA rigs. A look through the CPC catalogue will give you a lot more information than I could. A very useful - and nice - guy to talk to about fabricating bits
of antenna support hardware from steel is Brian at Barenco
<www.barenco.co.uk> Chris
On 14/11/16 13:36, 'Noel Matthews'
noel@... [ukmicrowaves] wrote:
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Steel box section masts
Noel G8GTZ
I’m currently reworking my VHF/UHF & microwave /p system based around a Land Rover and wonder if it is practical to use standard steel box section (preferably galvanised) as a single mast section with rotator and antennas / transverter on top (using box section rather than pole gets over problems of it rotating when being raised / lowered). I’m thinking of using a 60 * 60 * 3 mm steel section about 5 metres long which would be mounted / pivoted at about 1.8 mts off the ground on the roof rack. 1.8 mts of pole would be extended beyond the roof rack when on site and used to pull up the remaining 2.8 mts to the base of the rotator above the pivot point. I am not that mechanically minded, but looking at various commercial systems it would appear that the mast would be stable enough once raised (my own tennamast has a 40*60 top section), but the big question I have is whether it would actually strong enough or would it bend with the head load during raising and lowering process. If yes, then what can I do – increase the box section size or is it better to increase the wall thickness or what? Any help / advice / alternative solutions appreciated – and where can I buy galvanised box section in 5mt lengths? 73 Noel – G8GTZ
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Re: Activity List for the UK Microwave Group Low Band Contest Sunday
Barry Lewis
Neil, Well thanks for your efforts on 13cms and you can at least bask in the glory of being our best DX on 13cms on Sunday! 73 Barry As M0HNA/P Sent from my Samsung Galaxy smartphone.
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Re: Scottish Microwave Round Table
I’m more than happy to echo those sentiments. I diverted one of my normal trips back from Doha, Qatar via Edinburgh and had a very enjoyable visit to the GMRT.
I parted with some cash, learnt loads and met some very interesting people.
Thanks for putting the event on, certainly will be interested in attending in future years.
Mark G0MGX
From: ukmicrowaves@... [mailto:ukmicrowaves@...]
Sent: 14 November 2016 09:55 To: ukmicrowaves@... Subject: [ukmicrowaves] Scottish Microwave Round Table
I would publicly like to thank the organisers of the Scottish Microwave Round Table for a most enjoyable event. I hadn't managed to make it back since the first one some 5 or 6 years ago. I was pleased to see the same enthusiasm for the higher bands that I saw back then. Limiting the size of the event helps to retain the unique atmosphere of the GMRT.
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Scottish Microwave Round Table
SAM JEWELL
I would publicly like to thank the organisers of the Scottish Microwave Round Table for a most enjoyable event. I hadn't managed to make it back since the first one some 5 or 6 years ago. I was pleased to see the same enthusiasm for the higher bands that I saw back then. Limiting the size of the event helps to retain the unique atmosphere of the GMRT.
I was extremely impressed by the 'microwave' dinner on Saturday evening. There was nothing microwaved in the quality of the food and presentation. Lovely! Added to that was the musical entertainment from the 'Microwave Band', consisting of John, Nadine and Ian. Sadly Chris was unable to join the 'quartet' this year. I don't have a musical ear, but I did enjoy the traditional music and the ballad of the car for sale........... Thank you, GM. 73 de Sam, Acting Chairman, UKuG Sent tomorrow from my time machine
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Re: Wednesday night 23cm Digifest
Martin A Hall <gorrell77@...>
Hi Neil,
I like the principle behind your suggestion, although I would suggest a
minor change. As far as I’m aware I’m the only “northerly GM” active on
23cm, and suggest that if you have a “slot” for this area it is right at the
start – evenings are not good for suitable aircraft movements, and drop off
rapidly as the evening goes on - by 2130 they are normally down to one or two
per hour, so the earlier the better. Having written that, I have to
mention that unfortunately I usually work Tuesday, Wednesday and Thursday
evenings, so am not normally available.
I’ll be delighted to try QSO’s with anyone in AS range, which is as far
south as IOx3 if you have a reasonable take-off to the north, and at least as
far south as IOx2 if you have a very good take-off my way (better under enhanced
conditions), with daytimes being best simply due to a greater probability of
suitable aircraft, and my availability. Happy to set up skeds, and will
announce on this reflector when I am in or around the shack. My broadband
does get up to 2 Mbs at times, so KST works, and if I’m around you’ll also find
me on the Microwave chat.
CQs are usually hopeless from here on 23cm, though I’m happy to put out a
signal on request in a particular direction.
Good to meet quite a few members of this reflector in Burntisland at the
GMRT and have a chat.
73,
Martin
GM8IEM – IO78HF
From: Neil neil@... [ukmicrowaves]
Sent: Saturday, November 12, 2016 1:03 PM
To: ukmicrowaves@...
Subject: Re: [ukmicrowaves] Wednesday night 23cm
Digifest
Hi Simon, sounds good. Perhaps best to announce on the reflector about a firm
operating schedule with times, modes, frequencies and beam headings, a few days
ahead, it would gives others an indication of where to find us and whether there
is a chance we'll be beaming their way. The schedule doesn't need to be as
specific as this, but for those without KST access, it would be very hard work
to know when best to look for me. So if I was planning a long evening on 23cm, I might say something like: G4DBN IO93NR08 23cm 250W/18dB KST or 07777 999999 During the listen-only periods I would monitor and record a 192kHz segment of the band and watch the waterfall while the rotator pans back and forth, so that would be a good time to beam my way and call me. Skeds via KST preferred, so others can see any variances from the plan, or via SMS text for those without KST or KST2me. Changes to the schedule would also be announced on KST, and I'd put out a KST message announcing each change as listed, something like: +++ CQ 1296.168 MSK144/15 1st QTF 345 +++ All sounds terribly organised, but with very tight beam patterns on UHF/SHF, general CQs are hopeless. Giving advance warning via the reflector would ensure that others can plan ahead, with KST for more immediate skeds/notifications. Neil G4DBN From: ukmicrowaves@... [mailto:ukmicrowaves@...]
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Re: Wednesday night 23cm Digifest
simonchettle
Hi All
Following on from Neil’s example below is my personal availability schedule
(yes I know I must lead sad life). I will be both monitoring and TXing
throughout these periods. When possible I will announce on KST.
Presently I am unable to beam West due to neibours 30ft (and growing) hedge
until I move the mast.
Operating Schedule
Band: 23cms Frequency: 1296.165M Mode: JT 65C TXing on the even Minute. Initial Beam Heading: SE
Time in the Shack:
Mondays 14:00 – 16:00, 20:00 – 21:00, 23:00 – 00:00. Tuesdays 14:00 – 16:00, 23:00 – 00:00. Wednesdays 14:00 – 16:00. Thursdays 14:00 – 16:00, 20:00 – 21:00, 23:00 – 00:00. Fridays 14:00 – 16:00, 20:00 – 21:00, 23:00 – 00:00. Saturdays 23:00 – 00:00. Sundays 14:00 – 16:00, 20:00 – 21:00, 23:00 – 00:00.
These are the most probable times however subject to
domestic requirements
Hope to contact people on a more random
basis
73s
Simon
From: Neil neil@... [ukmicrowaves]
Sent: Saturday, November 12, 2016 1:03 PM
To: ukmicrowaves@...
Subject: Re: [ukmicrowaves] Wednesday night 23cm
Digifest
Hi Simon, sounds good. Perhaps best to announce on the reflector about a firm
operating schedule with times, modes, frequencies and beam headings, a few days
ahead, it would gives others an indication of where to find us and whether there
is a chance we'll be beaming their way. The schedule doesn't need to be as
specific as this, but for those without KST access, it would be very hard work
to know when best to look for me. So if I was planning a long evening on 23cm, I might say something like: G4DBN IO93NR08 23cm 250W/18dB KST or 07777 999999 During the listen-only periods I would monitor and record a 192kHz segment of the band and watch the waterfall while the rotator pans back and forth, so that would be a good time to beam my way and call me. Skeds via KST preferred, so others can see any variances from the plan, or via SMS text for those without KST or KST2me. Changes to the schedule would also be announced on KST, and I'd put out a KST message announcing each change as listed, something like: +++ CQ 1296.168 MSK144/15 1st QTF 345 +++ All sounds terribly organised, but with very tight beam patterns on UHF/SHF, general CQs are hopeless. Giving advance warning via the reflector would ensure that others can plan ahead, with KST for more immediate skeds/notifications. Neil G4DBN From: ukmicrowaves@... [mailto:ukmicrowaves@...]
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Re: Activity List for the UK Microwave Group Low Band Contest Sunday 13th November
Neil Smith G4DBN
.... that time when some of the blue paint on the 13cm masthead relay has gone brown and both contacts are now open circuit..... Called out to work again this morning, so started very late. Fired up on 13cm with full steam for a smoke test, forgetting that the BIG relay was on the 23cm kit, and the PSU was set to 30V. Something well over 120W into one of those weeny SMA jobs. Hmmmm. FET current went up for a couple of seconds, then dropped from the usual 45A. Quick flip back to receive. No signals on 13, and the dump resistor in the PA isolator was very very hot. Checked PA, filter, isolator, all good. Dropped the mast, found the still-hot relay decided, it was dead, swapped the 9cm relay for the 13cm one and managed ONE QSO on 13cm just before the end of the session. Also a few on 23cm. Time for a rebuild, and back to a single Spectrian until I find another big relay.... Good fun this ham radio stuff. Neil G4DBN
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Re: Mutek 432e
GORDONJ REASON <gordonj.reason@...>
The cost is nothing ...
On 12 November 2016 at 20:53 "'Keith D. Le Boutillier' keithl@... [ukmicrowaves]" <ukmicrowaves@...> wrote:
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Re: Mutek 432e
Keith D. Le Boutillier <keithl@...>
Hi Gordon
Many thanks for putting a Fet in the post for me it is much appreciated. Please let me know the cost and I will reimburse you.
Many thanks
Keith GU6EFB
From: ukmicrowaves@... [mailto:ukmicrowaves@...]
Sent: 12 November 2016 18:40 To: ukmicrowaves Subject: Re: [ukmicrowaves] Re: Mutek 432e
A Fet in the post for you ! Best Wishes , Gordon . The stamps were given to me .......! It should work well if you use it ..... please let me know ..........
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Re: Mutek 432e
GORDONJ REASON <gordonj.reason@...>
A Fet in the post for you ! Best Wishes , Gordon . The stamps were given to me .......! It should work well if you use it ..... please let me know ..........
On 12 November 2016 at 09:26 "keithl@... [ukmicrowaves]" <ukmicrowaves@...> wrote:
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Re: Mutek 432e
Dr. David Kirkby - Kirkby Microwave Ltd <drkirkby@...>
On 11/12/16 09:26 AM, keithl@lebs.org.uk [ukmicrowaves] wrote:
Hi GroupI would avoid eBay, especially if from China, since there are far too many counterfeit semiconductors on eBay. -- Dr. David Kirkby Ph.D CEng MIET Kirkby Microwave Ltd Registered office: Stokes Hall Lodge, Burnham Rd, Althorne, Essex, CM3 6DT, UK. Registered in England and Wales, company number 08914892. http://www.kirkbymicrowave.co.uk/ Tel: 07910 441670 / +44 7910 441670 (0900 to 2100 GMT only please)
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Re: Wednesday night 23cm Digifest
Neil Smith G4DBN
Hi Simon, sounds good. Perhaps best to announce on the reflector
about a firm operating schedule with times, modes, frequencies and
beam headings, a few days ahead, it would gives others an
indication of where to find us and whether there is a chance we'll
be beaming their way. The schedule doesn't need to be as specific
as this, but for those without KST access, it would be very hard
work to know when best to look for me. So if I was planning a long evening on 23cm, I might say something like: G4DBN IO93NR08 23cm 250W/18dB KST or 07777 999999 During the listen-only periods I would monitor and record a 192kHz segment of the band and watch the waterfall while the rotator pans back and forth, so that would be a good time to beam my way and call me. Skeds via KST preferred, so others can see any variances from the plan, or via SMS text for those without KST or KST2me. Changes to the schedule would also be announced on KST, and I'd put out a KST message announcing each change as listed, something like: +++ CQ 1296.168 MSK144/15 1st QTF 345 +++ All sounds terribly organised, but with very tight beam patterns on UHF/SHF, general CQs are hopeless. Giving advance warning via the reflector would ensure that others can plan ahead, with KST for more immediate skeds/notifications. Neil G4DBN From: ukmicrowaves@... [mailto:ukmicrowaves@...]
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Re: Wednesday night 23cm Digifest
Tony G4NBS
Totally Agree Simon which is why I started asking if there was a frequency for MGM so that random QSO might happen rather than being tied to the internet. Seems 165 has been unofficially adopted for 2m and up. I've got feeder issues at the moment so only able to be on a couple of bands and use transverters so can only monitor one band for noise. Advanced notice via this media would definitely increase likelihood of success. Good luck and hope to see you! 73 Tony. G4NBS
On 12 Nov 2016, at 09:03, Sam Jewell jewell@... [ukmicrowaves] <ukmicrowaves@...> wrote:
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Re: Activity List for the UK Microwave Group Low Band Contest Sunday 13th November
Derek Brown G8ECI
Good morning all, I will try and be QRV from JO03, Although only having 10 Watts at the ant socket so far and also need to get the Pre Amp sequencer finished. If I am able to get on, will anounce intention on ON4KST Otherwise details are# G8ECI Qth JO03AI 23cm 10 Watts 23 Ele Tonna (Seen better days) 73 es dx
On Saturday, 12 November 2016, 9:31, "G3XDY g3xdy@... [ukmicrowaves]" wrote: Thanks for your inputs, here is the activity list for tomorrow's contest
on 1.3, 2.3 and 3.4GHz, which runs from 1000-1400. Full rules are here: http://www.microwavers.org/files/2016-mwrules.pdf Best of luck to all taking part. This is the final event of 2016 and I aim to get the results and overall table for the year into December's Scatterpoint. 73 John G3XDY UKuG Contest Manager Callsign: G3UKV Locator: IO82RR Bands: 1.3, 2.3 and 3.4 towards the end. (swapping feeds with 2.3G) Talkback: 2m SSB (preferred), KST and 1.3G also direct. Callsign: G4ZTR Locator: JO01KW Bands: 1.3GHz, 200w, 2 x 60 el Talkback: Direct CQ and ON4KST Callsign: G4DBN Locator: IO93NR08 Bands: 1.3GHz 250W 44-ele 2.3GHz 60W 1m dish or 40-ele (2320 and 2300) 3.4GHz 16W 1m dish Talkback: KST or 2m SSB Times: whole session Callsign: G1DFL/P Locator: IO91NM 1.3GHz 10W 44Y WiMo 2.3GHz 1W 60cm Offset with WA5VJB feed Talkback: 144.175MHz SSB, direct CQ on 1.3GHz, ON4KST, and 07713 432632 Times: The last hour - 1pm to 2pm only. Callsign: M0HNA/P Locator: IO91RF Bands: 1.3GHz 250W 67ele 2.3GHz 60W 0.9m dish 3.4GHz 15W 0.75m dish Talkback: direct CQ on 1.3GHz, ON4KST (23cm M0HNA-1, 9&13cm M0HNA-2) Callsign: M0XIG Locator: IO90mx Band 1.3 GHz 10w Tonna 55 ele Yagi Talkback ON4KST direct CQ on 1.3GHz Tel No: 07780992564 Times: Various throughout Callsign: G3XDY Locator: JO02OB Bands: 1.3GHz 400W 4 x 23ele Yagi 2.3GHz 100W 0.8m dish 3.4GHz 20W 0.8m dish Talkback: ON4KST, direct CQ on 1.3GHz Times: Up to 1230 --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus
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Activity List for the UK Microwave Group Low Band Contest Sunday 13th November
John Quarmby
Thanks for your inputs, here is the activity list for tomorrow's contest on 1.3, 2.3 and 3.4GHz, which runs from 1000-1400. Full rules are here:
http://www.microwavers.org/files/2016-mwrules.pdf Best of luck to all taking part. This is the final event of 2016 and I aim to get the results and overall table for the year into December's Scatterpoint. 73 John G3XDY UKuG Contest Manager Callsign: G3UKV Locator: IO82RR Bands: 1.3, 2.3 and 3.4 towards the end. (swapping feeds with 2.3G) Talkback: 2m SSB (preferred), KST and 1.3G also direct. Callsign: G4ZTR Locator: JO01KW Bands: 1.3GHz, 200w, 2 x 60 el Talkback: Direct CQ and ON4KST Callsign: G4DBN Locator: IO93NR08 Bands: 1.3GHz 250W 44-ele 2.3GHz 60W 1m dish or 40-ele (2320 and 2300) 3.4GHz 16W 1m dish Talkback: KST or 2m SSB Times: whole session Callsign: G1DFL/P Locator: IO91NM 1.3GHz 10W 44Y WiMo 2.3GHz 1W 60cm Offset with WA5VJB feed Talkback: 144.175MHz SSB, direct CQ on 1.3GHz, ON4KST, and 07713 432632 Times: The last hour - 1pm to 2pm only. Callsign: M0HNA/P Locator: IO91RF Bands: 1.3GHz 250W 67ele 2.3GHz 60W 0.9m dish 3.4GHz 15W 0.75m dish Talkback: direct CQ on 1.3GHz, ON4KST (23cm M0HNA-1, 9&13cm M0HNA-2) Callsign: M0XIG Locator: IO90mx Band 1.3 GHz 10w Tonna 55 ele Yagi Talkback ON4KST direct CQ on 1.3GHz Tel No: 07780992564 Times: Various throughout Callsign: G3XDY Locator: JO02OB Bands: 1.3GHz 400W 4 x 23ele Yagi 2.3GHz 100W 0.8m dish 3.4GHz 20W 0.8m dish Talkback: ON4KST, direct CQ on 1.3GHz Times: Up to 1230
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Re: Mutek 432e
keithl@...
Hi Group
Many thanks to Chris and all who responded with help and advice on a suitable gasfet to replace the one that has failed in this pre-amp I will now source a suitable replacement on Monday.
Thanks again.
73 Keith GU6EFB
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Re: Wednesday night 23cm Digifest
SAM JEWELL
And some of us are in GM for the Round Table. Sam, G4DDK
On 12 Nov 2016, at 08:39, 'John Lemay' john@... [ukmicrowaves] <ukmicrowaves@...> wrote:
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Re: Wednesday night 23cm Digifest
John Lemay
Simon
I sympathise with your unanswered CQ calls, but ………..
I didn’t know that you were calling, I didn’t know on what frequency, I didn’t know where you were beaming …. Etc.
Finding QSO partners on 23cms (and above) is quite a needle-in-a-haystack job, and we need all the help we can get to make successful contacts. Given that your internet connection is poor, I think your best bet is a prior announcement of your intentions on this reflector, rather in the way that John G4BAO set out the proposals for a Digifest. Given a bit of advance warning, and hopefully a few emails from people who will look your way, the success rate will improve.
Regards
John G4ZTR
From: ukmicrowaves@... [mailto:ukmicrowaves@...]
Sent: Saturday, November 12, 2016 01:20 To: ukmicrowaves@... Subject: Re: [ukmicrowaves] Wednesday night 23cm Digifest
Thanks all for comments
In future I will post on this reflector and KST (When flaky broadband allows – penalty of living in a rural area).
May I humbly suggest that if you are in the shack, and as the JT modes are MG, some CQ calls may be responded to.
I set up the system to-night on 23 calling CQ – no response.
I hesitate to make the following comment - If those of us who are around during daylight hours turn on our Transmitters it may, in the future, assist in protecting our band allocations. To quote from G3PHO “ A Thousand receivers make no noise”
73s Simon G8ATB
From: Neil neil@... [ukmicrowaves] Sent: Friday, November 11, 2016 8:14 PM To: ukmicrowaves@... Subject: Re: [ukmicrowaves] Wednesday night 23cm Digifest
It is certainly worth a try, particularly if you can aim end-on to a set of planes on a glide-path or a busy route. I find I get best scatter results from distant 23/13cm beacons when the planes are actually BEYOND the beacon, so i ins't scatter as such, but a reflection. I get good reflections from GB3DUN and GB3ZME and Martlesham even when there are no planes between me and the beacon, but plenty to the south of them. Lots of experimentation needed to determine exactly what is going on I think! Happy to do a test almost any time so long as I get a bit of notice, working from home most of the time at present, so I am available at coffee breaks and lunch and most evenings. Neil G4DBN
On 11/11/2016 20:04, Edward Harland g3vpf@... [ukmicrowaves] wrote:
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