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Re: Testing ATU-100 help
Hi Immo.? I am highly delighted that you have pointed the extra turn out to me.? To be quite honest I cannot believe it as every time the wire goes through the hole of a transformer counts as a turn.? I need to go back for a day to school to learn to count again silly me so no need to worry at all Immo.? Pleased you've told me like Dave G8PTN? as he has been helping me also and so glad obviously of any help especially running into problems that require to be sorted out.? Thankyou Immo and David G8PTN kindly.
73s? G4RVH |
Re: Testing ATU-100 help
hi David,
my remark should not be a criticism to you or your build nor your age as I¡®m at nearly the same age. I built and repaired several of these tuners and recognised a difference between applied power and displayed power. Root cause was the 11th turn on the binocular core. Even ready built ones from china have nearly all 11 turns!!!! So my remark only should help you to get an even better result. nothing more!
Best 73, Immo |
Re: Testing ATU-100 help
Hi David,
I won't bother, but your photo shows a transformer wound with 11 (eleven) windings... Why? look here:? /g/ATU100/message/2535?
You may let is as it is and change the content of cell 31 to '11' or get one turn out from core and let cell 31 with '10'.
Have fun!
Immo, DL5KB |
Re: Testing ATU-100 help
Hi David?
Your a Genious,? very well done in spotting my STUPID mistake.? Definitely not intention I can assure you.? So glad you spotted the mistake.?
So as soon as I get time I will drop back onto the project. So after correcting the small SMD resistors hoping to see 5Vdc from ground to the little silver round holes either side of B1 & B2 all being well and then should be able to do the proper test. I will keep you posted but will give the whole board a thourourly good check out and clean with Isopropanol? 73s? G4RVH |
Re: Testing ATU-100 help
Hi David,
I forgot to mention that I also noticed that the 34k resistors for the "RVS" and "FWD" potential divider appears to be 68k on your board.
Perhaps that is intentional?
?
An extract from the schematic is shown below, with 68k series and 34k to ground.
R3, R4 = 68k
R20, R21, = 34k
?
73, Dave
?
? |
Re: Testing ATU-100 help
Hi David,
I hopefully see what the problem is. Unfortunately, you have connected to the incorrect points for RB1 and RB2.
The connections should be to the pads shown below.
?
You have currently connected to the 10nF capacitors associated with the 34k? resistors shown below.
?
Also, looking at the display image you sent, it looks like there may be an offset, but that is a minor issue for now.
I don't know if the have a PIC programmer, the offset can be adjusted in the HEX file.
This issue was covered recently in the following thread.
?
73, Dave
?
? |
Re: Testing ATU-100 help
Hi David.? Gosh so grateful for your guidance on this problem.? The volts on those two little silver soldered pad B1 & B2 is 1.72vdc.
But the resistors I've used are to big so must chance them as don't think there touching the pads enough.? No excuse for age 77 as been using SMD for years now having built a Hermes Transceiver.? The Display is all ok displaying everything on screen? 73s G4RVH |
Re: Testing ATU-100 help
Hi David,
There should be internal weak pull-ups on all three button signals, there is also an external pull-up on the ¡°TUNE¡± signal. ?
The extract from the code for the internal pull-ups is shown below.
From the datasheet, the typical weak pull-up current is specified as 140uA, with VDD = 5V and VPIN = VSS. This equates to an equivalent pull-up resistance of around 36k?. I would therefore expect to see VDD = 5V on all three pins if the buttons are not pressed. I assume the PIC is working correctly. Without pressing any buttons, does the display show the correct information at power up? ?
If I remember correctly it was quite fiddly soldering to the B1 and B2 connections on the bottom side of the PCB.
73, Dave |
Re: Testing ATU-100 help
Evening Dave.? I managed to find time today to test the voltage on the Jumper TUNE via rb0 pin 21 via R5 1K resistor while powered up and shows 5V dc?
The other 2 that connect RB1 Auto & RB2 Bypass under the board don't show 5 V dc
Which is now making me wonder if I have a grounding fault so will have to do further testing.
Thanks for your help.? Should I also get 5V dc on those B1 & B2 under the board as well
73s Dave? G4RVH
|
Re: Testing ATU-100 help
Sorry for the delay Dave as we have been on holiday in our touring caravan and just returned today.? Been to Tewksbury and Corwen North Wales but thank you very much for pointing me to some tests that I can now carry out.? I will of course let you know how I get on.? Regards david? G4RVH |
Re: Testing ATU-100 help
Hi David,
I tested the ¡°FAST TEST¡± mode when I first built the ATU100, and it worked as expected. There are internal pull-ups on all button signals.
With the unit powered up, and without pressing the buttons, the signal end of the switch should measure 5V, indicating it is connected to the PIC.
When the button is pressed the signal end of the switch should measure 0V.
Perhaps, also try the ¡°TEST MODE¡± by pressing the ¡°Bypass¡± and ¡°Auto¡± buttons whilst powering up the unit. This allows you to manually step through the relays.
When all relays are activated, the supply current will be around 0.25A, dependant on the supply voltage. 73, Dave |
Testing ATU-100 help
It's only me again? David G4RVH. Before coming away on holiday in the caravan I finished off the ATU-100 pcb.? So went to do a quick test by switching on the unit at the exact same time as switching on the Auto and Bypass and Tune buttons which ground the switches.? Anyhow it did not activate all of the relays to test that all of the 2N7002 Mosfets were grounding all of the relays to switch them all on at the same time.
So thought I would see if anyone can throw some light onto the problem to sort this issue out while I am away.
Much appreciate any help.? I will of course bell the whole circuit through when I return home.? Hoping it's just a quick fix.? Regards to all? 73s David? G4RVH |
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