Hi Bands board problem

Post Reply
N6ALT
 

Posts: 21
Joined: 02 Jan 2022, 20:02

Hi Bands board problem

Post by N6ALT »

I have finished building the Hi Bands Board from UpTech store on AE. I have power output on all bands and receive on all bands except 10 meters. Does this point to the relay for 10M? Any suggestions would be greatly appreciated.

Joel
N6ALT
DL2MAN
 

Posts: 706
Joined: 30 Dec 2021, 19:18
Contact:

Re: Hi Bands board problem

Post by DL2MAN »

Either Relay or more likely: Bad solder joint on one or both of the 2 Toroids....
Please triple check your solder joints there.

73 Manuel; DL2MAN
N6ALT
 

Posts: 21
Joined: 02 Jan 2022, 20:02

Re: Hi Bands board problem

Post by N6ALT »

Hi Manuel,

Thanks for the response. I have thoroughly checked the solder joints of the relay and the toroid cores and even reflowed them so the problem isn't there, (also there is continuity between the pads of the toroids). Would there even be any power output on 10M if the toroids were not soldered correctly, I have 2.5 watts out on 10M just no receive. I think I will place a order for some relays.

Joel
N6ALT
User avatar
ve2rn
 

Posts: 55
Joined: 13 Jan 2022, 20:45

Re: Hi Bands board problem

Post by ve2rn »

I have also some problems with 2 hi bands boards and one classic , trouble started when trying 10M. Now even with the original lo board no transmit is possible and with the classic i have blank screen when connecting the board. I think there is a serious problem with the boards. 3 differents rf boards and 2 different main this is more than i except . I have assembled many lo bands boards without problems before am i the only one with these problems? At this moment i do not know if the second main is affected because it is not in my hands. I am in contact with up tech but i am still in the phase of getting questions basic like "have you change the menu option to classic?" it will be a long long long process. BTW i need to mention that the main board i am using is one from RXXXXXs and i have change the connector to round ones like used by up tech.
Sylvain Naud
VE2RN
DL2MAN
 

Posts: 706
Joined: 30 Dec 2021, 19:18
Contact:

Re: Hi Bands board problem

Post by DL2MAN »

@N6ALT
Sorry, this was a misunderstanding then: you have output power even on 10m, but no RX ?
Then it's most likely not related to rf board.

How did you test RX ?

@VE2RN
You need to be careful when changing boards to always select the right one in the menu. Happened to me as well to have selected the wrong one.
Once you tx with the wrong band setup it tries to tx for example 20m through 10m filter or vice versa. This can blow the Fet and cause a chain reaction and take down the driver (on Mainboard) with it as well.

@both:
Both please carefully read the warning notice right above Index field on schematic:
Especially on 10m, it is EXTREMELY critical to have the filter tuned !!!!

73 Manuel DL2MAN
N6ALT
 

Posts: 21
Joined: 02 Jan 2022, 20:02

Re: Hi Bands board problem

Post by N6ALT »

Manuel,

"How did you test RX ?"

I hooked up a resonant antenna(s) for the Hi Bands and double clicked the encoder cycling through the each band while listening, I hear normal band activity, noise, on each band until I reach 10M then totally quiet even with a 10 m vertical hooked up. Yes I have changed menu 8.7 to Hi before I did any testing. I have between 4.2 to 3.5 watts output on all bands except 10M is 2.2 watts. I haven't done any filter tweaking yet.

Joel
N6ALT
N6ALT
 

Posts: 21
Joined: 02 Jan 2022, 20:02

Re: Hi Bands board problem

Post by N6ALT »

UPDATE,

I received my new relays from DigiKey and replaced the 10M relay, I also rewound two new toroids for 10M. I still have the same problem as first, I have power output on all the HI bands but only have receive on 20M and 15M. I have installed the original LO band PA board and it works great on both TX and RX on all bands, so I have to conclude that the HI band board from the UpTech store is somehow defective. I will contact Sunny and see if I can get it replaced unless anyone has a better idea.

Joel
N6ALT
DL2MAN
 

Posts: 706
Joined: 30 Dec 2021, 19:18
Contact:

Re: Hi Bands board problem

Post by DL2MAN »

N6ALT wrote: 15 Sep 2022, 15:55 I haven't done any filter tweaking yet.
And quote from the Schematic:
WARNING: The low amount of toroid windings makes tuning of the filters more important than ever ! Especially second harmonic notch needs to be carefully tuned with NanoVNA !!!Example: On 10m the difference between 4 turns distributed equally and 4 turns compressed is more than 5MHz difference in Notch Position!!!(...)
https://dl2man.de/wp-content/uploads/20 ... _86256.pdf
N6ALT wrote: 18 Sep 2022, 16:03 I will contact Sunny and see if I can get it replaced unless anyone has a better idea.
SO my reply will also be a quote, as I have posted my suggestion before:
DL2MAN wrote: 15 Sep 2022, 06:22 (...)
Both please carefully read the warning notice right above Index field on schematic:
Especially on 10m, it is EXTREMELY critical to have the filter tuned !!!!
(...)
Final thoughts on my side:
The (tr)uSDX was never meant to be sold as a completed unit, and it was never meant to support anything above 20m. Maybe your experiences show, that we should discontinue high bands support again....

73 Manuel; DL2MAN
Murphyv310
 

Posts: 52
Joined: 18 Apr 2022, 19:33

Re: Hi Bands board problem

Post by Murphyv310 »

[/quote]

Final thoughts on my side:
The (tr)uSDX was never meant to be sold as a completed unit, and it was never meant to support anything above 20m. Maybe your experiences show, that we should discontinue high bands support again....

73 Manuel; DL2MAN
[/quote]

Hi.
Please don't go down that route.
I modified a low band board to Classic and its been working beautifully since I did this in July.
There must be an issue with the board from Sunny. I've ordered one as well and will construct it on arrival. If it works then they must be OK. If not then they need to be rechecked before another batch is made IMHO.
Regards, Trevor. MM0KJJ
User avatar
ve2rn
 

Posts: 55
Joined: 13 Jan 2022, 20:45

Re: Hi Bands board problem

Post by ve2rn »

Murphyv310 wrote: 19 Sep 2022, 10:49
Final thoughts on my side:
The (tr)uSDX was never meant to be sold as a completed unit, and it was never meant to support anything above 20m. Maybe your experiences show, that we should discontinue high bands support again....

73 Manuel; DL2MAN
[/quote]

Hi.
Please don't go down that route.
I modified a low band board to Classic and its been working beautifully since I did this in July.
There must be an issue with the board from Sunny. I've ordered one as well and will construct it on arrival. If it works then they must be OK. If not then they need to be rechecked before another batch is made IMHO.
[/quote]
I agree to continue working and maby having problems with hi bands it is a learning process for beginners and if my tuning of the board was inadequate i accept the risk and will try to learn from that and will certainly not blame others for that. Sharing problems is a route to solutions, not give up.
Sylvain Naud
VE2RN
AC9YY
 

Posts: 133
Joined: 21 Mar 2022, 00:04
Location: Illinois, USA

Re: Hi Bands board problem

Post by AC9YY »

I recently got the hi board too and only installed the 10 meter coils and T1 and T2. I can transmit with a bit above 5 watts around 28.9 MHz, lower frequencies are a little less. I tried receiving on my OCFD which work great with my other 2 (tr)uSDX on the lo bands as built but I get no signals. When I get more time I will add the rest of the coils, test and report back. I did notice the efficiency isn't what it should be so will have to hookup the NanaoVNA and tweak the coils.
Murphyv310
 

Posts: 52
Joined: 18 Apr 2022, 19:33

Re: Hi Bands board problem

Post by Murphyv310 »

That seems very odd.
OK I realise I didn't make a high band configuration I went classic as they are the bands I mostly use.
So if 10 meters work in the classic configuration then 10 should work in the high bands configuration unless there is a component error or the program is wrong and 10 meters isnt getting accessed or perhaps swapped with another band which could make two bands incorrect. Just my musings.
Regards, Trevor. MM0KJJ
N6ALT
 

Posts: 21
Joined: 02 Jan 2022, 20:02

Re: Hi Bands board problem

Post by N6ALT »

Another update,

I have tweaked all the toroids and have achieved just under 5 watts on all bands with about 55% efficiency on all bands, but still no receive on 10M. I can hear band activity on all bands but 10M is dead. It's pretty simple actually, two coils plus one relay per band, it's kinda hard to mess that up, so there must be some defect in the board or the firmware. This might offer a clue, only on 10M I can adjust the bandwidth filter up and down with no audio coming from the headphones until I get to 3K then I get a loud hash noise but still no receive. Firmware issue?

Joel
N6ALT
AC9YY
 

Posts: 133
Joined: 21 Mar 2022, 00:04
Location: Illinois, USA

Re: Hi Bands board problem

Post by AC9YY »

N6ALT wrote: 19 Sep 2022, 19:45 Another update,

I have tweaked all the toroids and have achieved just under 5 watts on all bands with about 55% efficiency on all bands, but still no receive on 10M. I can hear band activity on all bands but 10M is dead. It's pretty simple actually, two coils plus one relay per band, it's kinda hard to mess that up, so there must be some defect in the board or the firmware. This might offer a clue, only on 10M I can adjust the bandwidth filter up and down with no audio coming from the headphones until I get to 3K then I get a loud hash noise but still no receive. Firmware issue?

Joel
N6ALT
2.00h for me. In my case it cannot be related to the other coils on other band positions because I only placed T1, T2 and the 2 coils for 10 meters. Hopefully tonight or tomorrow I can put in the rest of the coils for testing. I do however need to tune the coils for 10 meters still.

With 4 turns for L12 my second harmonic is around 32 MHz maximum with spacing out the windings, will try with 3 windings. I did have around 5 watts out.

Testing with 3 turns I am still only to 37 MHz, could L12 only need 2 turns? I can finally hear a little on the receiver on 10 meters because originally the dip was right near 10 meters instead of 2 times that frequency. My power and efficiency are way down too. 2 watts and 15% efficiency now. Could the capacitors be out of spec?

I have a classic RF board coming soon so I can also test that on 10 meters.
Attachments
Screenshot 2022-09-19 181755.png
Screenshot 2022-09-19 181755.png (102.26 KiB) Viewed 2652 times
DL2MAN
 

Posts: 706
Joined: 30 Dec 2021, 19:18
Contact:

Re: Hi Bands board problem

Post by DL2MAN »

Murphyv310 wrote: 19 Sep 2022, 10:49 There must be an issue with the board from Sunny. I've ordered one as well and will construct it on arrival.
I have the SAME Boards, as there is only one batch at the moment. I did my Tests with this Batch and they work.

Let me add a little more disclaimers here:
- Every small Problem will be magnified on the higher Bands, as everything becomes more critical. For Example: I hear OLED Noise again on 28MHz.
- RX Sensitivity is Lower on the higher Bands. Basically we have the same RX Sensitivity as on the lower Bands, but Noise Floor is way lower and we have no pre-amp
- Even a Minor mistuning has huge effect. It might be a matter of shifting a winding 1mm back and forth for fail or pass.
- For FDT86256 use PA Bias Max 160 for max efficiency.
- Determine Efficiency by external measurements, and Adjust RShunt in Menu, so displayed Efficiency matches externally determined Efficiency
- Don´t expect more than 70% Efficiency on the High Bands with FDT86256 on a perfectly tuned Filter Board.

All that said: 28MHz works on both of my PCBs (from Sunnys currently sold Batch) Classical and High Bands. I receive Signals and I can TX with 5W and 70% Efficiency, and I have good harmonic suppression.

Attached 2 Picture, so you can see, how odd the Coils can look if tuned to the right point:
Image
Image

Bottom Line:
If you do your Part on carefully Tuning, setting up RShunt, PA Bias Max and LPF Selection, it works with the above mentioned restrictions.

@AC9YY: Your above Screenshot shows S11 (SWR). Measuring Reflections with a 50 Ohms Device in a non 50 Ohms Filter is almost guaranty for failure.
Please perform measurement as described in the Filter Tuning Thread:
viewtopic.php?p=1686#p1686
or as shown in my Video:
https://www.youtube.com/watch?v=qN7hHsvcNMM

@N6ALT, try installing latest Beta Firmware from here:
https://dl2man.de/wp-content/uploads/20 ... /beta.html
73 Manuel, DL2MAN
AC9YY
 

Posts: 133
Joined: 21 Mar 2022, 00:04
Location: Illinois, USA

Re: Hi Bands board problem

Post by AC9YY »

Manuel,

You are correct, I thought I changed the display to LogMag, but did not. The below display is where I left off at 3 windings. The first dip is at 37.7 MHz and the second at 53.8 MHz. It really appears I may have to remove another winding, but not sure why. The windings are spread out as much as possible and any change I make with the winding spacing (tighter) I make on L12 makes the dip is at a lower frequency, as expected.

I just wound the coils for 12 meters and with the windings on L22 spaced at maximum it is very close (top graph). I took a winding off of L22 and now it is spot on with compressing the coil.
Attachments
Screenshot 2022-09-20 203435.png
Screenshot 2022-09-20 203435.png (103.09 KiB) Viewed 2508 times
Screenshot 2022-09-20 193319.png
Screenshot 2022-09-20 193319.png (113.29 KiB) Viewed 2514 times
AC9YY
 

Posts: 133
Joined: 21 Mar 2022, 00:04
Location: Illinois, USA

Re: Hi Bands board problem

Post by AC9YY »

Has anyone else tried tuning coils via the NanaoVNA yet for 10 meters?
LILO
 

Posts: 69
Joined: 12 Aug 2022, 09:15

Re: Hi Bands board problem

Post by LILO »

You are measuring S11 again. It shows nothing.
Read instructions thoroughly step by step and measure S21.
DL2MAN
 

Posts: 706
Joined: 30 Dec 2021, 19:18
Contact:

Re: Hi Bands board problem

Post by DL2MAN »

NanoVNA Crash Course ;)
viewtopic.php?p=3294#p3294
AC9YY
 

Posts: 133
Joined: 21 Mar 2022, 00:04
Location: Illinois, USA

Re: Hi Bands board problem

Post by AC9YY »

When selecting LogMag in the app it displays for S11 and S21 together, no other option. With the NanoVNA I can select LogMag for S21 which shows the same data as one of the graphs on the app.
Post Reply

Users browsing this forum: Bing [Bot] and 4 guests