21-03-2018, 02:07
Hi,
100 to 220uF is just fine.
On schematics, C3 have a value of 470uF mainly because of the possible use of a fan for the Radiation Shield.
Here a small trick, which help to avoid the inefficient 7809 regulator.
- If you have the 7809 already installed, remove it.
- On the TX board, do a shunt between input and output pins of the 7809 regulator.
- Take a step down converter module like the one below. They cost less than $1
![[Image: m6K-zF7pP4CF4DmAKCFp5Ig.jpg]](http://thumbs4.ebaystatic.com/d/l225/m/m6K-zF7pP4CF4DmAKCFp5Ig.jpg)
- Connect your power source to the module input, and adjust voltage output to 9V.
- Connect the output of the module, to TX power in.
- If you are using +Bat pin to monitor the battery voltage in a solar system, just keep it connected to positive (+) battery terminal.
I think you catch the idea...
100 to 220uF is just fine.
On schematics, C3 have a value of 470uF mainly because of the possible use of a fan for the Radiation Shield.
Quote:I noticed if you power the TX board without a battery but with a non stabilized power supply it could be necerssary to add an additional capacitor on the input of the 7809 voltage regulator.
Here a small trick, which help to avoid the inefficient 7809 regulator.
- If you have the 7809 already installed, remove it.
- On the TX board, do a shunt between input and output pins of the 7809 regulator.
- Take a step down converter module like the one below. They cost less than $1
- Connect your power source to the module input, and adjust voltage output to 9V.
- Connect the output of the module, to TX power in.
- If you are using +Bat pin to monitor the battery voltage in a solar system, just keep it connected to positive (+) battery terminal.
I think you catch the idea...