Just found these on The Amazon and ordered them to play with:
(No promotion or endorsement of Amazon implied. ?I can just get these next day from them¡)
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Ok understood... I have a few of the below in the parts bin so could potentially modify my sbitx to use this instead... slight overkill though... ;)
On Tue, 9 Aug 2022 at 12:24, Ashhar Farhan <
farhanbox@...> wrote:
Peter,
At present we use an LM33, linear regulator to drop 13.8v to 5v. This takes almost 1.5A current on rx.
With this mod, the radio is running cool and the current draw is less than 0.5A.
- f
What is the purpose of this mod or what is the issue... not quite following ....
See attachment !
On 09/08/2022 4:32 PM, Ashhar Farhan wrote:
Those are the ones. Any idea of the chip used?
MP2307 is the chip
Raj
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On 09/08/2022 12:49 PM, Ashhar Farhan wrote:
I swear I had sent an email on this an hour ago...
Anyway, I replaced replaced the LM338 with a switching regulator. This one was very inexpensive, less than a dollar. It is also very efficient and small. Unfortunately, I dont know what it is called!
I am attaching the pictures. There is a tiny pot on it that controls the output voltage. I added a 22 ohms, fat resistor to the output pins and adjusted the output to 5.4v. Then I took out the LM338 and installed this. The ground is a thick and very short connection to a mounting hole (I used desoldering braid). The input and output is wired to the LM338's pcb holes.
I am running this for a while before declaring victory.
If someone can identify the chip and the regulator, I will be grateful.
