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Soldato
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Of course - Didn't you suggest some places for me to go when I spent a fortnight in Woking? I don't know of any specific clubs in the area but I do get down to Ripley/Send a couple of times a month.

Hmm, yeah I do recall recommending someone some places near Woking.

I've ordered the official Foundation license book which has been updated for September 2019 onwards. I'll see what it is like when it arrives. Seems like you can do the exam online which suits me fine.
 
Commissario
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You can do it online but I believe you still have to do it at an exam 'centre'. There's also some practical work at Foundation level which needs to be done in an organised environment but it's all pretty basic. I don't know how much the Foundation has changed but it was possible to go from zero knowledge to having a licence in the space of a weekend. There's no real understanding required at Foundation, it's just recall.

/edit - Here's the current specifications and syllabus.
 
Soldato
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You can do it online but I believe you still have to do it at an exam 'centre'. There's also some practical work at Foundation level which needs to be done in an organised environment but it's all pretty basic. I don't know how much the Foundation has changed but it was possible to go from zero knowledge to having a licence in the space of a weekend. There's no real understanding required at Foundation, it's just recall.

/edit - Here's the current specifications and syllabus.

Cool. Sounds good. I've had a look through the syllabus and I seem to be fine on most of the high-level stuff. If I have to go to an exam centre then so be it. The book won't arrive for a week or two though so I'll have to wait till then to see how much I really know.
 
Associate
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Maybe getting somewhere.

Replaced the antenna with a Nooelec Balun-one-nine and approx 4m or bog standard tri-rated 0.75mm cable on each side (Red if you're interested :D) R4 on 198 suddenly appears and a whole load more stuff besides.

Beginning to look like the ATU has a fault of some sort which is not switching the antenna in circuit on receive. Off to scopes and circuit diagrams then!

As an update on this. I am now not sure what the issue is.

  • If i hook it up to the balun and tune to a good string station all is well.
  • If i then swap to the antenna tuner, I can barely hear anything
  • If i unscrew the PL259 connector and pull it back ever so slightly (so that the center pin is connected, but the ground isn't) the receive seems to kick into life
If i measure from the centre pin to ground, I get a short. However, looking at the diagram, this kind of makes sense as is shows it being connected like that internally.

EBN6zmQ.jpg

Any Ideas (Preferably not just "Bin it" though :p ) are most welcome.
 
Permabanned
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It would be better if the whole diagram was shown, but you will, and should, get a *DC* path to ground on the input and I presume, the output as they are grounded through L14 and T1. A *DC* path is *NOT* an RF path at relevant frequencies though!

I presume R47, CR4, CR3, C32, C33 and R4 & R5 are part of a metering circuit (rectification of RF) that's off the diagram. Similarly C29, C31, CR1 and CR2 etcetera? I would say an SWR meter?

Is C4 shorted (plates touching)? C5 and C2 not shorted? C6 not shorted? Should be an easy fix.
 
Associate
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Indeed. I have been away from this for so long that I keep forgetting the whole DC/RF thing :p

Full cct is here (not sure how readable it is though.)

6UF5K6F.jpg

I was thinking that it is a shorted cap, but the thing with it working when disconnecting the co-ax ground was throwing me. The ATU has an earth terminal and this is connected to a spike in the ground. I tried it with the chassis screw on the radio connected to the same place as well as leaving it disconnected.

Will have to see when I can get some time to go through the board and lift the caps one at a time.
 
Associate
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Looking at that drawing last night and it made absolutely no sense. After about 20 mins I had another look online and it seems there is another drawing for the same tuner. Mine is not made to the original drawing. New one is this.

efVskk8.jpg
 
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Have you checked the relevant relays are actually conducting on each band as you switch to it? I would look for power supply and mechanical issues as a start.You really need a signal generator or strong noise source on the input and then scope each output or look at them with an SDR. Manual tuners are much simpler to troubleshoot... ;) As Feek mentioned you may find the tuner has not got the bandwidth to tune an aerial down below Top Band.
 
Associate
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Going to check the caps etc this week with luck. Next most obvious step is to check the relay switching etc. as you say.

Also, after reading some of the online comments, it seems that there can be issues with noise on the control lines, but this is on Tx only. Grabbed a load of screened 4 core and have some ferrites to add to the control wire, so hopefully that will rule that out.

I was considering the Sig-Gen/Scope option, but the SDR may also be worth looking at.
 
Soldato
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Anyone taking part in the CQWW WPX over the weekend ?? I've just got a HexBeam, its only on pump up mast (12m Racal) at the moment so i'm quite excited to compare it to my old Cobwebb. If all goes well hoping to put it on a more substantial mast.
 
Commissario
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I've just got a HexBeam
Great news, I wonder which one you went with?
i'm quite excited to compare it to my old Cobwebb
Well you're going from a folded dipole to a 2 element beam so you should notice the extra gain and some directivity.
Anyone taking part in the CQWW WPX over the weekend ??
I'll be on but it won't be a serious entry from me, just giving away a few points really. My hex is down awaiting repair after the storms and all I've got up is my 30m dipole which I've connected my smarttuner to, just to give me *something* for other bands but it's not very effective.
 
Soldato
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Great news, I wonder which one you went with?

Well you're going from a folded dipole to a 2 element beam so you should notice the extra gain and some directivity.

I'll be on but it won't be a serious entry from me, just giving away a few points really. My hex is down awaiting repair after the storms and all I've got up is my 30m dipole which I've connected my smarttuner to, just to give me *something* for other bands but it's not very effective.

Hi,

I orginaly wanted the MW0JZE version because they look really well built, but one came up a few month old (with a G650c which was handy) at a really really good price. It is a EANtenna verison, I was a bit dubious at first because they don't get great reviews for build quality, but I looks quite well built to me. It's a G3TXQ design, which I think most are these days.

I'm not having a serious go at WPX but plan to be on all weekend - I've got nothing else to do!

Although the cobwebb is quite well known for quiet on RX, but i'm pleased to say the Hex appears to be better (probably due to the directivity).

I've been enjoying a couple of live streams too lately which may be of general interest to the group (they maybe a bit marmite depending on your thoughts on remote operating).

W2RE Has a couple of huge remote set ups:
https://www.youtube.com/watch?v=H9n1S57AZTk

DX Commander - prefer his antenna videos
https://www.youtube.com/watch?v=s6-4SMc2KXk
 
Commissario
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Yeah, I saw that version at Newark a couple of years ago and the big problem I can see with it is the way the spacer cords are joined to the elements as they're exactly the same as the ones I broke over and over and over again under very specific circumstances. Those were while running data modes at a high duty cycle with QRO during contests in the rain or snow. The corona discharge at the end at the end of the elements simply arced over and burnt out the cords which then caused the elements just to drop and hang. If you look at the 'broken aerial' tag on my blog, you'll see what I mean.

During the recent storms, the centre stub of my hex slowly lifted out of the plate after breaking free of the bush and then it folded over until it was hanging there, supported by the spreaders at the top and the coax at the bottom. Then one of the spreaders snapped and it all started looking like a very sad, drowned spider.

I've got it down and the centre stub is going back to Ant for a repair. I'm also going to buy the extreme weather kit and the upgraded 40m balun which gives extra bandwidth. The extreme weather kit is supposed to stop the spreaders from raising due to wind and sinking due to ice and snow. His aerial (without the 40m kit) is rated at 75mph and we had gusts recorded at 78mph just a couple of miles away.

I reckon it'll be two to three months before I can get it all repaired and back up.
 
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