Normal?

[shovenose]

Hello
I was measuring the voltage on the 12V 1A Linksys adapter I use with my Linksys WRT54G...
It only asks for a 12V 0.5A but I didn't have that, and I figured that a little extra would be perfect for what I plan(ned) to do with it...

I OCed the Broadcom CPU in the router to the max, and I put transit power for 71mW to 250mW...
And yes it's got DD-WRT on it...

Anyway, just for the heck of it I tested the output of the power adapter and it was like 15V ???
Now, I'm assuming the load from the router brings it down to 12V, but still, this seems a bit high!
Is that normal or is it something to be concerned about?
The router has been working fine for the past 2 weeks until today, when I decided I didn't need ti anymore so it's put away...

Still wondering whether I should replace that power adapter?

[Scenic]

Re: Normal?

unregulated linear powersupply?

[Krankshaft]

Re: Normal?

Sounds on point for a 12V unregulated wall wart. All of the older Linksys routers I've opened had voltage regulators right on the input anyway.

My oldest BEFSR41 Version 2's power supply had no diodes in it they were inside the router. It always used to crash when line voltage sagged by a few volts. Took me forever to figure out until by chance one day I decided to hook it up to a Variac. A regulated switch mode supply fixed it.

The newer models are shipping with cheap switch mode supplies as a cost cutting measure less copper for the high frequency transformer and less iron. Whether they rely on the regulated output of the supply and delete the internal regulator on those models I'm not certain.

If the output for the supply is 12 volts you can be certain there's internal regulation the ICs most likely want 5 or 3.3 volts.

[weirdlookinguy]

Re: Normal?

At those power levels you're probably looking at very high tx error rates for the wifi.

It's all about finding the right balance between performance and stability when you start fucking with transit power and CPU speed on these Linksys-es (what is the plural of Linksys?)

[shovenose]

Re: Normal?

Yes, I did notice a few Tx errors... is that because of the transmit power?

[weirdlookinguy]

Re: Normal?

A low amount of errors is to be expected. Right now looking at my DD-WRT status page, for the last 3 days the tx stats are:

2436945 OK, 66 errors

That's a .000027% error rate on transmitted packets. I am running at 50 mW, which is the default power rate for this router (Linksys E2000). WRT54G has a default rate of 71mW I believe.

Check your percentage of tx errors (and let us know, I'm curious). You can pump a pretty high mW rate out of the earlier revision WRT54Gs before they start getting wonky.

This thread makes me want to recap my old WRT54GL. It was a damn good router before it started getting unstable.

[shovenose]

Re: Normal?

I put it away for storage (in the closet) so I don't know the percentage, but it wasn't very many errors, just a few...