18Watt.com

I just picked up an 1946 Phillips tube amp radio and want to add a phono input to it.

I just don't know where to start,

I'm thinking the easiest was would be adding it to the volume pot but the problem is that it also controls the power switch if you turn it all the way to the left so I don't know which leads are power and which are audio.

Also it is a rat's nest in there since there is no type of board at all,

I can take pictures if that would help

-Thanks

This isn't a question related to the 18 watt amp which is one of our constraints on this forum.

Let me send you on your way with something constructive, though. You may be able to get a schematic diagram for your radio at http://www.photofactondemand.com/index.asp Next Google "phono preamps" for relevant info. Frankly I doubt what you're out to do is practical, though it can be done with effort.

Good luck,
KennyO

I hate to be the bearer of bad news here, but... I'm afraid this thread won't last long... hopefully it will long enough for you to get this message.

First, this whole board is dedicated to one specific musical instument amplifier (The Marshall "1974" 18-Watt), and it's derrivatives... thus talk about a radio is severely off-topic and the moderators prefer to keep this board pretty much on subject.

Second, good news is that the volume control connections come off the side of that volume control, while your power switch is mounted on the back of it, with the power wires coming off the back of that. so they are separate in that sense.

Bad news is, considering that it is a radio, and you want to add a phono input, you'll need another switch and another tube to boost the phono signal and give it the proper RIAA EQ so it sounds right (see the back of most RCA tube books for that circuit) if you wish to keep the radio as a function too.

As it's a "rats nest" in there to you, that tells me that your experience is probably minimal on these types of circuits... and that can be very dangerous to your own life and health. More than likely this radio would be a shock hazzard outside of its case and probably won't directly support an extra tube either.

You can e-mail me off-list and we can talk about this more if you like though.

Wow i opened up my gramp's age old radio, i have 3 of the tubes with me right now, let's see here; DAF 40, DK 40, and a DL 41.
I would like to know aswell if i could do something like this.

That's a battery tube radio, and you won't find anything much of use to make a guitar amp, let alone a Marshall 18W type amp. It's actually probably worth more left as it is. So eBay it and buy yourself an 18W amp kit.

mad_cow wrote:I just picked up an 1946 Phillips tube amp radio and want to add a phono input to it.

CurtissRobin wrote: This isn't a question related to the 18 watt amp which is one of our constraints on this forum.

Correct. This doesn't even appear to be a guitar amp question.