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Getting started on 23cm


#1

After spending a few hours reading the 23cm topics on this reflector I decided a few days ago to get QRV on 23cm for S2S activations. Being completely new to microwaves, I’m looking for some advice.

I’ve just ordered a 23cm transverter and Yagi and will soon have the following kit available to take:

  • SG-Lab 23cm XV (2W output) and 2-el PCB antenna
  • 13-el 23cm Yagi (f/g 15.6dBi, beam 30 degrees)
  • Yaesu FT1D 2m/70cm handy
  • FT817, mic, paddles, LiPo
  • Sandpiper 2m Yagi (for talkback?)
  • Modified camera tripod (with 1m ali pole on top)

I will be operating mainly in G/LD and maybe G/NP (my house move from Bucks. to south Cumbria has been delayed, but – with a new buyer lined up – should be in May now).

From comments (e.g. Adrian G4AZS, Andy MM0FMF) it looks like a lot of (non-DX) contacts from SOTA summits is possible and practical with a ‘23cm lite’ FM-only set-up (handy + XV + PCB ant, e.g. resting on trig point or handheld) – presumably provided you post alerts and spots in advance.

On good-weather days (dry, not too windy at summit, ha ha!) I would take the tripod and the 13-el Yagi (0.46kg good, but 1m long on my rucksack(?) – I don’t want to spend time assembling and disassembling a Yagi at the summit – my circulation isn’t that good any more). From LD it looks like I could get into GM, Wales and the Midlands with 2W and the 13-el Yagi. Do most folk rely on spotting or getting 2m/70cm stations to QSY?

Regarding modes, am I right to say SSB is the most popular, then FM, then CW (Does anyone CW? Would anyone CW on request?). So would take the 817 for SSB/CW.

Is the 2m Yagi of any use here? On 2m I find my Diamond RH770 telescopic very effective with the handy. Is talkback really needed only for ‘difficult’ bands, like 10GHz?

Are contacts mainly S2S or do many home-based chasers have 23cm antennas? Sounds like FM chasers could be either H or V polarization. Switching polarization is trivial with the PCB antenna but not very practical with my tripod pole and H-oriented 13-el Yagi. I assume most/all SSB/CW mode stations are H-polarized.

Although I’m normally a HF CW activator, I would like to focus on 23cm and play with my new toys for the Lake District SOTA weekend, 18-19th. May. I had hoped to be living in south Cumbria and activating LD summits well ahead of that weekend. But now we’ll be lucky to move house in time. My wife will /need me to do stuff round the new house/Can’t wait to get me out of her hair/**delete as appropriate. So, I should be modest with my plans.

I think I’ll stay close to home (in case XYL calls) and activate only my (future) local summit, Arnside Knott (LD-058), which I can drive to in 10 mins and walk up in 15, and be QRV mainly or only on 23cm (SSB/FM/CW).

I see others plan to be 23cm QRV too for that weekend (G1ZAR, G0HIK, GX4ARF, MM0FMF, G4AZS, …) so hope it will be a fun day (days).

Thanks for reading this far. Comments on my assumptions & specific questions or any general advice on 23cm operation would be welcome.

73, Andy


#2

The key to anything “odd” in SOTA is to make a lot of fuss before hand to attract attention. If they don’t know you will be out with 23cms then they wont know to make an effort to work you.

It is surprising how well 1W of 23cms FM from a handy can work, especially with one of those small PCB antennas. But 2W of SSB into a small Yagi is a whole new game of opportunities.

Also, print a list of some of the more likely 23cms beacons / repeaters etc. so you have something to check your RX frequency against.


#3

The key to 23cm as Andy MM0FMF says is to have some waiting chasers, notifying by e-mail personally rather than just the SOTA alerts.

When activating I follow a pattern so the 23cm chasers know I am on the summit because I have worked 2m / 4m etc so the next is 23cm.

Keep the kit simple to increase reliability, every connector is a potential to go wrong.

This is what I use.


Everything 23cm is in the box, the antenna can be rotated between H & V. It is all driven by a handi, not much weight.

This is me in action, a fishing pole gives a little better take off for local obstacles.

In case you want to know what is in the box, sg-labs transverter, 4cell LiIon batt, a fuse, switch and LED. The antenna has only one SMA connector to the transverter, likewise the connection to the handi has only 2 connectors.

There are a few issues, most operation tends to be on 1297.5 MHz FM, the IF is 145.5MHz the 2m calling channel, there is enough leakage on the coax to the transverter than a local 2m station thinks you are calling on 2m. With the G/LD summits this is not a big issue because there are few local stations and they know what is happening, but now I am in G/SP it is becoming an issue and I will have to move to a quiet channel. Most G/LD is Vertical FM. I rarely get 4 QSO on 23cm, so you need some other bands to complete the summit.

Currently I am 22/55 G/LD on 23cm and as area I think it is 41/55. There are a few activators that now have 23cm on the Western side of the Lakes.

73 de

Andrew G4VFL


#4

Hi Andy

I have just returned home having completed a sucesful 2m, 23cm and 13cm FM activation of Mt Taylor VK1/AC-037 and a summit to summit contact with Compton VK2HRX/1 at Black Mountain on 1296 MHz.

All chasers were within a 30 km radius. Liaison frequency 146.500 FM.

In the pictures below my 23 and 13cm antenna is a log periodic (850 MHz to 6 GHz). For this activation the IF is a dual band HT.

Lightweight VHF-SHF activation

Good luck with your 23cm adventures.

73 Andrew VK1AD


#5

This thread is inspiring me to continue with the vary nascent and fledgling 23cm activations I have done…2 actually.

I mated the SGLab transverter to my KX3 and had some reasonable success with the supplied PCB antenna.

I’m coactivating G/LD-003 with M0NOM during the Saturday of the LD weekend and I’ll bring my 23cm stuff along.


Paul
W6PNG/M0SNA


#6

Andrew,
Are you running the transverter straight from 4 cells without voltage regulation?
I do like the arrangement for mounting on a fishing pole.
73.
Stuart


#7

Thanks everyone for your comments and advice.

The 23cm SG-Lab transverter and 13-el Yagi arrived in the post recently and I’ve done a few Rx tests at my local SOTA summit G/CE-005 (Wendover Woods) and on Dunstable Downs.

CE-005 is not very microwaves-friendly being flat and surrounded by tall trees in all directions (wet now after rain). Dunstable Downs is largely obstruction-free though sadly not a SOTA summit.

I tried the rear-mounting Yagi on a tripod and on my 3m telescoping pole. The pole bends too much causing the Yagi to droop in the forward direction (though moving the base of the pole compensates somewhat). The tripod wants to fly away in high winds but I’ve solved that with a) a sandbag hanging on the hook under the tripod. I’m using the sand right now but for SOTA activations I would empty the bag and fill with rocks at rocky summits, or b) at grassy summits, three guy rope pegs with ties for each leg of the tripod.

I have re-purposed a bike handlebar bag as a 23cm ‘Go Bag’ with FT817, transverter, 2 LiPo’s, mic & earphones, and which hangs on the Yagi pole clamp and rotates with the Yagi so that the coax feeder doesn’t get wrapped round the tripod extension pole. 30cm of Velcro round the top of the bag strap and Yagi clamp stops the bag from falling off.

I only need to connect the feeder to the Yagi and two DC cables to the LiPo’s to be QRV. The Go Bag fits snuggly into my larger rucksack (with plenty of room still for Bothy bag, water, etc).


The Yagi, tripod and extension pole fit in a 1m-long nylon bag (intended for musicians’ microphone stands) which goes over the shoulder.

On tests I heard the GB3MHZ beacon (near Ipswich, Suffolk) 3/3 at CE-005 (140km away through wet trees) and 5/5 at Dunstable Downs (125km away). GB3FM repeater (Farnham) was 5/8 at Wendover Woods. The GB3DUN beacon was 5/9 at Dunstable Downs (it’s very close by!) and 2/2 at CE-005 (through wet trees).

I’ve impressed by the accuracy of the frequency of the SG-lab XV comparing it to beacon frequencies.

But I’m yet to transmit!

I hope to participate informally in the 23cm contest on the 19th March. But I would like to get QRV ASAP to check the XV Tx is working, mic level is okay, etc. and wonder if anyone in this region is planning (or is willing) to go 23cm QRV in the coming days or weeks? I’m flexible on which day of the week but would prefer daylight hours if possible.

73, Andy


#8

Having got QRV on 23cm for the very first time only yesterday (with my new SG-Lab transverter and old FT817) I took part in the RSGB 1.3GHz contest this evening from Dunstable Downs. I made 5 contacts in the first 20 minutes of the contest. Exchanges to and from were all 5/9 and all my contacts said how very strong my signal was. It just shows what you can do with 2W into a 13-el Yagi only 5ft off the ground provided you are at a good hilltop location.

All the contacts were under 50km away so no Dx records broken on my first microwave contest but for me that wasn’t the point of the exercise. There were other (weaker) stations that I probably could have worked but it was cold and dark and time to go home and celebrate that everything was working well with a glass of something.

I’m no contester but I probably will participate again in this contest especially as it gets lighter in the evenings to get more experience of operating on 23cm. I’m looking forward to SOTA activations and doing summit-to-summit contacts. Having carried the kit (minus the sandbag for the tripod) in a rucksack and long shoulder bag up to Wendover Woods (G/CE-005) trig point several times now, I think the setup is practical for doing more serious SOTA summits.

The Lake District SOTA weekend in May will be a great opportunity as many on this reflector have declared their intention to be 23cm QRV.

73, Andy


#9

Well done Andy.
You may not like contests, but they do provide an opportunity to try out equipment, or to qualify a summit on the less populated bands. I was out this evening, but not on a SOTA summit this time, but once the nights get a bit lighter I shall be. I think most people who have tried the SG-Labs have been surprised how well 2W travels. Look forward to a S2S with you in a contest, or during the LD weekend.
Which Yagi are you using?
73…Stuart


#10

Thanks Stuart,


“Dual” from antennas-amplifiers.com in Bulgaria. My one looked used (the aluminium bar has lots of scratches and marks and some of the directors are not quite aligned) but it seems to work well.

73, Andy


#11

Hi Andy

Try making your own 23cm Bi-Quad. My record with the Bi-Quad at 2.5 watts is 272 km. :slight_smile:

Good luck with your future 23cm activity.

Andrew VK1AD


#12

Hi folks,
I would like to thank the people who contributed to this thread. It inspired me to try 23 cm, and indeed on March 31, I managed my first 23 cm contacts from the summit of Prairie mountain, near Calgary. Indeed it seems to have been the first recorded 23 cm SOTA contact in Canada!
In similar fashion to most of the people here, I was using an FT817 as the IF radio, an SG transverter and a home-brewed bi-quad antenna (thanks Andrew VK1AD).
From the summit of Prairie Mountain I was able to hear a beacon about 180 km away, and was able to make contacts on ssb (VE6EN) and FM (VE6MB and VE6EN) into Calgary. I was not sure of the exact distances, but after entering the data into the SOTA database it informed me that VE6EN was 51 km away, and VE6MB was 48 km away. I was not able to hear VE6BGT who was about 180 km away, near the beacon, despite him using a 21’ dish and 700 watts!
I didn’t manage to get any pics on Prairie Mountain (it was snowing and rather busy), but I do have a picture of testing my equipment on the side of the road, east of Calgary where I could hear the Beacon at ground-level.


The Calgary Amateur Radio Association is soon holding a Flea Market and associated learning sessions. Two of the three topics are on operation above 50 MHz, so maybe there will soon be more stations to contact.

Ian
VE6IXD