Regarding Joe's suggestion of using the Raduino's LM7805 to power the TDA2822:
One objection I would have is the extra wire, needs to be dealt with every time?
I unplug the Raduino.? Though not a big deal.
A spare LM7805 on the bottom of the main board is more convenient.
A 25 ohm 1/2 watt resistor in series with the 12v Vin lead of the Raduino's LM7805?
should solve the problem with extra heat.? And/or a heatsink on that LM7805.
Add caps to ground on both ends of the resistor to kill any tuning clicks.
I would think those caps could be fairly small, but some here report success using
electrolytic caps of several hundred uF's.? I haven't bothered, no clicks.
Adding that wire for a regulated 5v from the Raduino adds opportunities for
Nano clock noise to get into the receiver.? Keep it short, put a 0.01uF cap at each end.
Can't use the 78L05 that gives the IRF510's their gate bias,
because that regulator must be shut down during receive.
Jerry
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On Thu, Mar 15, 2018 at 04:26 pm, Jerry Gaffke wrote:
Could work, first time this was suggested.
An extra wire, the Raduino regulator would get hotter.
?
On Thu, Mar 15, 2018 at 03:39 pm, Joe Puma wrote:
Jerry has the group discussed pulling 5v from somewhere else like use the 5v that powers the Raduino? Maybe temporarily until they can get a regulator and or new WX chip??
?
