Hi, roof box now takes 25 MHz reference and 430 MHz IF. No more 2.4 GHz at 70 m coax !!!
MY QO100 SETUP
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Hi, the updated block diagram.
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Program with no BOD, set it to 1.2 MHz internal clock and program ADF in setup mode only (ADF needs to be programmed once in your case).
Feed ATiny13a with 3V3 from ADF board.
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Program with no BOD, set it to 1.2 MHz internal clock and program ADF in setup mode only (ADF needs to be programmed once in your case).
Feed ATiny13a with 3V3 from ADF board.
PA3FYM As far as I can see ATTINY13A has 9.6 MHz, 4.8 MHz (this I use) & 128 KHz internal clocks.You mean to set 9.6 and use divide by 8? I program it 500 mS after power up. I do not program it again. I power it from 3.3 V from ADF PCB.My opinion is that BOD is required as the problem is due to slow VCC rise due the RC that exist from the long power supply cable. The unreliable operation is that it fails to initialize the ADF most of the times. Once it initialized it works fine with no problems later.
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Set the SUT fuses to 10 for slowly rising power.
Page 25 >
http://ww1.microchip.com/downloads/en/DeviceDoc/doc8126.pdf
VY73 DB8TF
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Set the SUT fuses to 10 for slowly rising power.
Page 25 >
http://ww1.microchip.com/downloads/en/DeviceDoc/doc8126.pdf
VY73 DB8TF
I have it allready from the begining but it does not solve problem. I have low 0x79 & high 0xFF and I plan to set the high fuse at 0xFB. TNX !!!
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SV1BDS What you can do is put a zener diode in series with the ADF power supply so that when the voltage exceeds a certain value, the voltage on the ADF + ATTiny is 'suddenly' there, e.g. zener of 5.6V.
If you want to try (is very simple, just solder the zener ;; -), bear in mind zener needs to be connected 'reverse' compared to a diode. So 'anode' to ADF power input, 'cathode' to cable/external power supply.
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To solve the (similar) BU500 power up problem with slowly rising voltage i use a small relais which is connected to VCC via a series resistor and a parallel capacitor.
So this relais switches the VCC to the BU500 after about 1 sec (when the C is charged)
and the VCC is stable.
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To solve the (similar) BU500 power up problem with slowly rising voltage i use a small relais which is connected to VCC via a series resistor and a parallel capacitor.
So this relais switches the VCC to the BU500 after about 1 sec (when the C is charged)
and the VCC is stable.
I have already think of it as my last solution.....TNX again !!!
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Only good relay is a coax relay. Is not needed here, so use solid state solution ; -)
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Only good relay is a coax relay. Is not needed here, so use solid state solution ; -)
Yes my irfp4905 is almost finished ... May I have to use a coax relay
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Hi, the brown out do the job !!! 10/10 success. I saved my coax relay
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What did you do with the BOD? Disabled it?
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What did you do with the BOD? Disabled it?
I enabled it at 2.7 V as I use 3.3 V. Fuses are now 0x79 low and 0xFB high.
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The 10 MHz to 25 MHz converter is now in a box. A 74HC390 dividing by 2, the xtal ladder and a MAV11 MMIC. An another MAV11 is required to drive the LNB.
Two 10 kohm resistors are used at input pin #1 of the /2 divider one to GND and the other to +5V in order to accept sin wave as input.