Can you build a switchbox?

[Motor Boater Bill]

So, a switchbox is just a bunch of components built into a circuit, right? Does anyone know if it would be possible to build your own switchbox from off the shelf componenets?

 

[rodbolt]

Re: Can you build a switchbox?

if your an electrical enginneer with an electronics background,sure. its only some SCR's<capacitors and transistor circuits, along with some voltage controlling circuits. other than that its no worries. the hard part is that dang potting materiel removal.

 

[Barnacle_Bill]

Re: Can you build a switchbox?

Sure, if you got a schematic and parts list.

 

[DHPMARINE]

Re: Can you build a switchbox?

I think they said yes.<br /><br />DHP

 

[rodbolt]

Re: Can you build a switchbox?

depends on the definition of the word "yes"

 

[Laddies]

Re: Can you build a switchbox?

I saw a switch box at Fondlac with clear potting in it and you could see the componates and read the Mercury parts numbers so we ask the instructor if we could buy the parts and he said we couldn't, we wrote down a couple of numbers and tryed to order them went we got back to the shop. The numbers were marked cannot identify on the shipping invoice--Bob

 

[prolinews]

Re: Can you build a switchbox?

mercury would lose millions if we could make our own. At least most of their parts are cheaper than omc.

 

[Motor Boater Bill]

Re: Can you build a switchbox?

There are at least a couple levels to the yes or no, it seems. First, you might not have to be an electrical engineer if you have a schematic and parts list. But if those are not available, then you'd have to reverse engineer it, a good bit more difficult. Second, if the parts are proprietary, then it would be even harder. Still, it seems like an interesting puzzle, doesn't it? Anybody ever tried it?

 

[rabidfish]

Re: Can you build a switchbox?

Rapair/CDI does it... I am certain you could also.<br /><br />Let us all know how you make out!

 

[WillyBWright]

Re: Can you build a switchbox?

Give the credit card to the wife and tell her to go shopping. Then warm-up the oven to 240 degrees. Place the switchbox upside down with a pan under it and the potting should melt out. I imagine it'll be a stinky process, so you'll have to come up with a logical explanation when your wife gets home. I wouldn't eat the next batch of brownies that comes out of there, tho. Some components you can get at Radio Shack. The bad ones are sometimes visually obvious. But Murphy's Law means you'll have a bad one you can't see, or you can't get it at Radio Shack.

 

[Motor Boater Bill]

Re: Can you build a switchbox?

WillyB, it sounds like you have done this? Realistically, a used toaster oven from the junk store will be cheaper than sending my wife out with my credit card--then I can plug it in outside. How about the parts? Are they all pretty much off the shelf or are some proprietary? One problem for me in pursuing this is that my switchbox WORKS to I'm not about to stick it in the toaster! I'm just curious about this--of course if mine dies I'll have nothing to lose at that point! Thanks to all for contributions, ideas and experiences on this topic.

 

[Kenny Bush]

Re: Can you build a switchbox?

Sure...Go to the Home Depot, down the electrical isle, they will have everything you need. Just ask the guy in the orange apron.....He can help you with all the design and installation........<br /><br />....but, all it is is is is a CCA which you could outsouce overseas, epoxy coat and sell it to us cheap......

 

[WillyBWright]

Re: Can you build a switchbox?

Haven't done it myself. I just asked the right person a few years ago. I've been itching to try it myself.

 

[rodbolt]

Re: Can you build a switchbox?

hello<br /> just be aware that potting material burns. if you dont belive it look at any merc or jonnyrude after the regulator lights up

 

[Paul Moir]

Re: Can you build a switchbox?

A while ago, Iboat member nordy reverse engineered his '99 Johnson 2-cyl CDI pack when it fell victim to moisture intrusion. It was a very simple CDI circuit with an rev limiter designed around a F to V converter. It had pretty good circuit protection, but otherwise it wasn't rocket science stuff.

 

[Motor Boater Bill]

Re: Can you build a switchbox?

Anybody ever seen a schematic?

 

[Paul Moir]

Re: Can you build a switchbox?

Here's the J/E one:<br /> Click here.

 

[Silvertip]

Re: Can you build a switchbox?

I see what are likely three proprietary circuits in this schematic. Two of those are ICs. Merc will likely have the same problem. These would not be available off anyones shelf so would also need to be reverse engineered. Even less likely you could get a schematic of those parts unless you knew someone on the inside. For the other stuff go to Radio Shack.

 

[Paul Moir]

Re: Can you build a switchbox?

LM2907 is a freq to voltage converter (used for the rev limiter) and a MOC3021 is a opto-isolator (LED-TRIAC) for the overtemp limiter. Not RS parts I know, but not exactly hard to get - digikey or mouser would fix you up with them. The only thing I see in there that's the least bit tricky is the transformer, which you would have to spec a sub for yourself. <br />Even more interesting, if you eliminated the overtemp limit and rev limiter, you wouln't have much of anything left in your black box but a couple SCRs (6A, 600v), a bridge rectifier, capacitor and a handful of shaping and protection components.<br />Like I said before, this isn't rocket science.

 

[ozarkjeep]

Re: Can you build a switchbox?

I made one last year for my 1970 80HP merc.<br /><br />it starts and idles fine, but I havent been able to get it to run right. IM not sure if its the engine OR my home brew Ignition.<br /><br />I have thought about trying to market the deal, would people buy a magic box that replaced the switchbox and coil?