Voltage reducer question

[yurtle]

And FWIW, I tried the two cart batteries on the memory wire, but that may have lead to the death of my 30 amp reducer. I thought since it had a negative common it would be OK. NOT. Maybe with a relay?

[Fegarex]

Originally Posted by yurtle

And FWIW, I tried the two cart batteries on the memory wire, but that may have lead to the death of my 30 amp reducer. I thought since it had a negative common it would be OK. NOT. Maybe with a relay?

I never really gave that any thought. With the reducer "off" the negative side of it may turn to 36 volts too? I was going to run a dedicated + and - wire for the memory but that may conflict with the switched wire.

[Sergio]

Originally Posted by yurtle

My radio in my sig DOES have a dedicated memory wire, as did every radio I've had since the 70s.

Yurtle, no radio manufactured this century has a dedicated memory wire.

Please read the instructions for your radio, the yellow wire provides all of the power to the radio.

The red wire is just a trigger wire (very low current) to signal the the radio to power ON.

When the radio is OFF, the head unit draws a small amount of current from the same yellow wire to keep the settings.

The auto industry made that change decades ago to reduce the amount of current required for the the ignition switch harness.

[yurtle]

https://www.google.com/search?tbm=is...ZdgKs8N7Jl_KM:

Memory wire keeps all presets. Without it, no memory. What's so hard to understand?

[yurtle]

OK, you may be right. If I understand you, the "memory" wire is low current, until the radio is turned on? Next time I drop my console, I'll hook up an ammeter to see if you're correct. I may be living in the past?

[Sergio]

Originally Posted by yurtle

https://www.google.com/search?tbm=is...ZdgKs8N7Jl_KM:

Memory wire keeps all presets. Without it, no memory. What's so hard to understand?

Apparently what You cannot understand is that without the "yellow wire" the radio will not power up at all.

Where do You keep reading the words "memory wire"?

[yurtle]

I did do an experiment to prove that my unit can go a few seconds without power, and not lose its memory. A relay can power the radio with a small battery, then switch it to reducer, which will trigger the relay.

[Sergio]

Originally Posted by yurtle

I did do an experiment to prove that my unit can go a few seconds without power, and not lose its memory. A relay can power the radio with a small battery, then switch it to reducer, which will trigger the relay.

I mentioned the relay on a previous post but did not go in details since it depends on the type of batteries, the radio load (playing loud) and the radio capacity of maintaining the settings during that brief brown-out.

If Your radio has enough capacity to keep settings at your normal operation levels, a SPDT relay would work.

COM - Radio yellow wire.
NO - Converter output.
NC - Battery tap.

The relay coil would be wired with the Radio red wire so the relay turns ON when the converter is ON.

[yurtle]

Originally Posted by Sergio

Apparently what You cannot understand is that without the "yellow wire" the radio will not power up at all.

Where do You keep reading the words "memory wire"?

I acknowledged I'm probably wrong.

[Sergio]

Originally Posted by yurtle

I acknowledged I'm probably wrong.

It is all good, I did not see your post when I was typing.

This is just a recurring issue since many moons ago radios did work as you mentioned but with all of the high density harness and computerized electronic push button ignitions, manufacturers had to change how they power the radios to prevent problems with modern ignition systems.