Short update of nothing

The constant rain has started again and this week so far we got 74 mm of rain making everything soaked and there is water everywhere.
No major update actually as nothing new has happen.
Was intended to make some changes to the amplifier last weekend but the supplier sent the wrong parts so I need to make that at a later stage.
Had some communication with Jim regarding what happen and he never encountered anything similar but there must have been some sort of oscillation causing extra heat desoldering the capacitor cable and burning the decoupling caps.
He has made an update regarding the low frequency gain circuit that i will make to ensure it will eliminate this problem in the future.
Will also change all fans to 24 V ones to get some more airflow through the heatsink and around the components on the board.

During my search for lower noise figure I have ordered some SAV-541+ from Microcircuit which will hopefully arrive this week.
Have found some designs using these transistors but the use a wide band input circuit and I do not really like that and will try these in the YU1AW design and rebuild the DC circuit.
They seems to be very similar and hopefully there will be a minimum of redesign.


Some time ago I got boards for the VK5DJ rotor controller that I had some problems getting to work properly but tried once again to get it to work and now its up and running with HH-12 encoders and it seems to work ok.
My intention was to use a 4*40 LCD display but have had some problem getting them to work but its all OK with 2*16 ones.
Investigated more  thoroughly but it seems like the 4*40 display is broken because I cannot get it to work with an Arduino either so I ordered some new ones.

Walked around in the garden the other day and was planning for a hedge on the south side of the house where we today have a lot of trees.
I don´t like large trees close to the house and they will be removed next spring and a fence will be put up and a hedge planted.
This will clear out some area which could be good to put a dish for higher frequencies or if I make a larger one like 7 meters or so to be able to operate on 70cm with it as well.
Have not decided yet on how to proceed but will most likely make a foundation for a mast when digging to remove the root systems from the trees and to plant the hedge.
I like the concept of OE5JFL with his offset dish construction.

8970 fixed

Opened up the noise figure meter today to check what was the problem and what causing the not so pleasant smell.
It turned out to be a short circuit in a decoupling capacitor in the 20MHz circuit causing the -15V supply to drop and the burned was an inductor that was slightly burned but still OK.
Replaced the cap but as the backup battery has been poor lately I left the box open and will get a new battery tomorrow and replace.
Repaired the burned 70cm preamp and it works but the noise is slightly higher but it seems stable so I am good with that.

Tested a 2m YU1AW and a 23cm G4DDK as well and it correlates to earlier measurements so nothing else seems wrong with the meter.

2m YU1AW Preamp

G4DDK 23cm preamp that I have spent some time with.

Weekend work

The last week has been occupied with a lot of work and other non ham related things.

Worked some on the moon this weekend but low activity on Saturday but higher on Sunday morning when it seemed to be better propagation.

Did work the Swaziland expedition on Saturday morning quite easy and they were at strongest -15dB but later in Saturday morning the polarization shifted completely and I could not read them for hours.

This morning I could read them all the time and worked 8 other stations in total including a nice contact with Kjell, SM7GVF who was really strong with his single yagi.

Interesting to compare what other reports of signal levels of different stations and it seems like I do hear very well.

As I live without any neighbors or large areas of QRM the noise level is very low but it still seems like there is something causing noise from my own house but have not found it yet.

At one time during the morning I discovered a new noise that I never heard before but when I at one time went outside i saw the robot lawn mower close to the antennas and after parking it the noise disappeared.

This is not a big problem as it is soon time to take it in for storage during wintertime.

Registered on livecq for reporting from MAP65 in real time and it worked without any problems.

Discovered that when listening on a specific frequency in MAP65 it decodes lower signals then when listening on another frequency.

Occasionally I could detect 3DA0MB at -27dB or something similar when I tuned the MAP65 the their QRG but the wideband decoding could not detect them at lower levels then approximately -25dB.

I also need to rebuild my preamp I blow last weekend as well because the one I use now does not start at some times when switched to RX.

It happens rarely but I missed a few decodes due to that this morning and that´s not acceptable.

The problem is that I need to fix the noise figure meter before so I can tune it properly but will hopefully find the time to do that this week.

High winds and rain

High winds stopped me from any operation Sunday night at moonrise so the contest part 1 is over.

In the contest I worked 21 stations with some new and some worked before.

Highlights was the good own echoes as high as -6.3dB and good signal reports from VK4EME.

Called a lot of CQ but lacks a lot from the reduced output power.

Worked all I heard and called for except W7MEM whom I called many times during Sunday morning but he just saw weak traces of me.

From what I know now the smallest stations was a couple of 2 yagi stations including KA1GT and LU8ENU that was a lot stronger this time compared when I used 2 yagis.

So the antennas seem to work as predicted but I will most likely lower the mast and go for open wire feeds next summer.

During sun noise measurements it was clear it did not perform as well as it could but it’s a part of the process to constantly improve the station performance and reliability.

Worked yesterday evening at moonrise and it worked really well with good echoes and some stations in the log.

Went to bed and slept for a few hours and went up at 2Z to work in the US window but the propagations seem to been really poor.

A lot of stations was a lot weaker then the night before but also very low activity.

Don´t know if it was the ongoing reg1 UHF contest that caused this or people just don´t like to be up early in the morning.

Occasionally the propagation was fair but US stations was in general weak and many reported bad faraday rotation.

Worked in total so far 26 stations and when I looked all 6 continents for a WAC.

The only problem I had was actually PST rotator that occasionally froze and had problems communicating with the controller.

Don´t know if the problem was at the sw side or the Arduino side and it was not a big problem just irritating when the antenna don´t track.

Will try work tonight at moonrise too and see if someone ells are QRV.

Indicator working again.

The problem with the indicator errors was found and fixed.

Sometime during the night did the rotator turned 2 full turns causing the indicator cable to the elevation to stretch and squeeze so at first it broke a wire for the elevation signals and that´s when I lost the elevation indication and when I continued beaming following the moon to the westthe cable stretched further causing a short circuit between the 5V feed and ground which made the azimuth indication to also quit working.

Found the problem and fixed it temporarily and now all is good again.

Strange that I did not noticed that but most likely when it was going over the 180-degree point as I then noticed it started going in the wrong direction but stopped it and forced over 180 manually.

Nevertheless, sometimes during the night it happened and I need to exchange that cable at some point but I had limited time during the day today so it was starting to get dark and the rain has also started again.

The rain causes some VSWR but nothing alarming so I am on the moon again.

Interresting night

So this was an interesting and eventful night.

Started listen at moonrise and the antenna behaves as predicted no problems there.

Heard HB9Q at -3 with the antenna beaming through a large oak tree and good echoes as best -6.3 dB and could detect my echoes with JT with as low as 25W.

Did work some stations before the contest started without any problems but when I tried to work JA6AHB I suddenly got high VSWR and the amp tripped.

Found that the TX relay in the mast has gone and also the preamp was broken but no problem I have a second set so just climb up and replace and I was QRV again.

Or that’s what I thought.

When power everything up again and TX testing a strange sound and some fireworks appeared in the amp.

Strange and it took me a few seconds to realize and to switch of but the output power was there the whole time.

Opened the box and found one of the short coaxial cables that acts as a capacitor on the output side on one of the transistors has come loose for some reason and the decoupling capacitors close by has burned away.

So I searched and found some caps in similar capacitor values but did not know their voltage capability but I tried and exchanged the broken ones and mounted everything back together again and it worked.

Limited the output power to 400W after that just to be safe but it worked Ok for the remaining of the night.

10 minutes before the contest started all stations suddenly disappeared and it took a while to understand that the rotor controlling sw had a default 180 degree stop which caused the rotor to starting to go around the other way to go over 180 degrees.

Forced it manually the right way and everything was OK again.

A few hours later I lost all stations on the moon again and this time the elevation indication broke down indicating 0 degrees that made the controller sw to try to elevate with the result of the elevation going to max.

Could not get the indication to work again so I continued without it as there was a clear night so I could occasionally go out and check where I was aiming and correct if necessary.

Continued with working with my 400W or so but it seemed slow and I only worked 7 stations in the contest and 4 before but heard a lot of stations so I was feeling confident I should work more.

Then again I lost the stations on the moon while working HB9Q in the contest and looked around to see what happened this time and you guessed it, the indication for azimuth was gone showing 180 degrees constantly.

Was able to finish with Dan but it took 1 or 2 periods extra to get the 73 through as the antenna was completely wrong direction and I needed to adjust by hand.

This stopped any more operation and I closed everything down and went to bed.

I hope the problem is in the Arduino circuit or I need to take everything down as the HH12 in azimuth is below the rotator and the rotor needs to be removed.

Will not do that today as there will be some family activities later but will check if the problem is in the arduino end later today.

But I starting to feel uncomfortable about the amplifier consistency and will try to source another one for the future as it´s actually a big difference if you work with 400W or a full kW.

So if you have or know of any please send me a mail.

If there will be any work tonight I don´t know right now as I need to check the indication before as tonight the weather will be overcast and no manual tracking possible.

Waiting for the moon

Now I am as ready as I get for this part of the ARRL.
Measured some sun noise and I measured approximately 13dB.
Seems like I lack 2 dB or so but as I use coaxial cables and I have not tested the preamp as the Nf meter broke down so I it could be ok as is.
I still think I have something generating some noise in my house as well because when I beam into it, the noise increases almost the same amount as the sun.
Will try to find that later tonight before the moon gets up.

I could not get Map65 to work with HPSDR so I use a FCD on 28MHz to avoid any overload.

Thought about using a SDRPlay but the I need HDSDR to run in parallel and I don´t want that.

It´s enough with HPSDR, WSJT, Map65 PST rotator and a web browser.

I also like to have a picture editing sw running to save screenshots of the QSO´s.

Will setup an additional screen later too.

The output power from the amp at transverter almost at max is 750W and that’s ok for now.

Needed to adjust the output indicator and when the fan kicks in and did run the amp without the case and there where massive feedback all over the place but non what so ever noted with the case on.

Have everything setup in the basement as I want to be as close the cables as possible but everything is possible to operate remotely so later on the rig and the amp will be seated here and I will operate from the shack upstairs.

Right now I want to stay close to the gear in order to learn how everything behaves when operating for a while.

Constant rain again.

It must be easy to be a weather man here in Sweden nowadays.

Nothing correlates with the predictions and now has the constant rain started again.

And as the frosting on the cake there is high winds too so no sun noise measurements have been able to be done this week as the antenna is constantly parked down the wind.

Almost finalized the amplifier yesterday but need to drill 4 holes for the TX input connector to be completely done and then test it but all switching and metering is working.

Maybe need to add some screening to the metering as there will be high RF inside the casing causing interference.

Added a lot of ferrites to all DC feeding cables and inductors on others going to the controller board.

I hope it will be enough but lets se when power it up.

Discovered I had put in a 6dB attenuator in series with the amplifier and this will reduce the input power to 6W when putting in 25 and that's a bit low so I might need to exchange that to 3dB in order to achieve full output power.

Used this settings last year with a TS811 who also have 25W out and still I had decent output power so I will try the 6dB and see how it will work before I make any modifications.

Funny how much I have forgotten about the amplifier in this short time but that must be an age thing for sure:)

Receiver configuration

Have finalized the transverter and the connection to the exciter for both RX and TX with all 25 W output and the reference locked oscillator in place.
One interesting thing is that when using the original oscillator the output power is slightly less.

I am convinced I have been able to use both Map65 and WSJT together with the Anan 10 before but now it seems impossible to get the Map65 to work.
Spent the hole evening yesterday trying to get this to work but no way would Map 65 get any I and Q signal in.
So I will go back to use the FCP+ or a SDR Play RX for Map65 instead.
Wil mount the FCD inside a screened box including a isolation relay so it would not be overloaded at TX.
Did use FCD for Map65 last year but just laying on the desk caused it to overload at TX so I would like to sort that out this year.
Once use to Map65 I could not even consider working without it as its very convenient to monitor the complete band at once identifying all stations.

Looked at the amplifier too last night and saw that it was far from done and I had just put it in the box without anything hooked up inside so I need to start that tonight but its not so complicated so hopefully I will finish it quickly.
The antenna system is also now in a high wind test as it suddenly started to blow quite hard with gusts as high as 20 m/s but so far it has coped with the wind really good and barely moves at all.

All cabeling done

So now I have done all the cabling.

The TX feed is a 20m 7/8" and into the house its 2m RFC600 which is also used in the other end of the 7/8" to the relay around the rotor axis.

Preamp and relay is mounted inside the triangular horizontal boom and RX Cable is a RG213.

All rotors and indicators are working but I have approximately 1 degree of on azimuth and 0.5 in elevation but will compensate for that in PST rotator.

Tested the tracking function built-in the K3NG controller but as my azimuth indication is 1 degree less than the real and tracking stops when within the set tracking accuracy the antenna is all the time between 1 and 2 degrees behind.
Was convinced I once saw an offset setting option in the K3NG controller software but could not find it any more.

Had some problem during the week with a broken cable and the HH12 azimuth indicator was oriented upside down so the indication went the wrong way but there is a reverse indication option in the controller so I just reprogrammed it.

The sun was very low when I finished the work today so could not measure any son noise so I tested with some beacon instead. SK1UHF which is the closest one behaved very strange with no clear peak or sideloobes but I discovered that problem before and I think it is due to reflections from surroundings as there is sheet metal roofs on both the barn and the carport which is in that direction.
OZ7IGY behaved a lot better which is close to 180 degrees in opposite direction.
It was too weak at the moment to show any sideloobes but peak width seems corresponds to simulations.

Did mount the daughter board for automated switching of 10MHz reference oscillator inside the Anan 10 which will be the exciter used for main RX and TX.

Completed the transverter too but it requires some rebuild adding a circuit on TX IF side as the output power did only reach some 18W and not the stated 25.
Not a big deal but the attenuators inside the amplifier is set for 25 W input so it’s more convenient to use the same.

Before I mounted the preamp in the antenna I was trying to measure the noise factor but when starting the NF meter, a familiar smell of burned electronics started to appear and increasing rapidly.
So something happened and now its indicating an error but got a tip from SM7FWZ this morning at our weekly 80-meter ring that it could be the power supply voltage regulators that has broken or short circuit causing traces on the PS board to burn.
Will check that later when I have more time.

Will continue with finalizing the transverter and insert the Apollo board allowing the transverter to use a 10MHz stabilized oscillator too.

The power amplifier needs some work too as last year when used it it had no cover which I added this year but need to add some inductors at some wires and make a new output cable and connector to fit the new housing.
It has no inbuilt relay for RX/TX relay as I have everything separated all the way up to the first antenna divider.

Have changed my idea how to switch everything and now I will switch the PA with the exciter and the transverter at the first sequence from the PA.
The transverter has also a built-in sequencer only used to delay the TX of the transverter to be the last event.