Toggle switches for vhf speaker

[jimi]

Any recommendations, being electrical numpty I thought i'd get two external speakers one inside & one outside and toggle between them with the input being from the jack plug out the vhf. Whats the best toggle type switch to do this? Ideally I just want 2 wires into the switch.

 

[Colin_S]

Maplins doubtless do something. Do you want the option of having both speakers on or just either?

 

[Robin]

Expert help needed here Jimi I think. The 2 external speakers will replace one single internal one (which cuts out when the external plug is used) and are mounted in parallel to give an impedance to match that of the set speaker. I'm no electronics/radio techie and hopefully one will pop up, but I believe the set speaker has a 4 ohm impedance which is matched by having 2 x 8ohm ones in parallel, thus switching one speaker 'off' is not an option. The simple option of one external speaker doesn't work because you probably then cannot hear the set in the cabin when you are transmitting, yet you cannot hear it in the cockpit without an external speaker, catch 22 and brilliant award winning design. It only works if you have easy access to the ext plug and simply have one ext speaker, pulling the plug on it will allow reversion to the set speaker when you are below.

 

[Joe_Cole]

If you just want to switch between "outside" and "inside" speakers then 2 x 4ohm speakers and a Double pole Double throw switch should do it. (Mind you that will be 6 wires at the switch)

Alternatively do what I have done. Cut a hole and mount an external speaker on the cockpit bulkhead. One speaker, that can be heard above and below deck. Much easier. (Just remember to turn it down at night if you are alongside another boat!)

 

[FullCircle]

Semi Numpty answer:

http://www.maplin.co.uk/Module.aspx?Modu...D=&doy=23m1


is a stereo speaker switch box which takes one input and allows to switch either of the other speakers on or off or both together. Yours for a tenner, and even you could fit it.

Jim

 

[FullCircle]

In fact, sod it, thats such a good idea, I am going to buy one now. Thanks Jimi.

 

[Robin]

[ QUOTE ]
If you just want to switch between "outside" and "inside" speakers then 2 x 4ohm speakers and a Double pole Double throw switch should do it. (Mind you that will be 6 wires at the switch)

[/ QUOTE ]

That option sounds ok but assumes you only want one speaker in use at a time and remember to switch from one to tother?


[ QUOTE ]
Alternatively do what I have done. Cut a hole and mount an external speaker on the cockpit bulkhead. One speaker, that can be heard above and below deck. Much easier. (Just remember to turn it down at night if you are alongside another boat!)

[/ QUOTE ]

Actually not too different to what we do. Because access to run the wires from our set to the cockpit was difficult, I did a temporary installation 3 years ago that remains today! We have 2 external speakers (8 ohm in parallel) plugged in, with one at the chart table and the other in the companionway/bridge deck, held in place very neatly with velcro, the wires are led in the join between headlining and bulkhead also on little stick pads. However the point is that the speaker works very well there and on a smaller boat could probably be heard both from the cockpit and from below. We used small plastic waterproof speakers bought in France for around £10 each, not the cumbersome V-Tronix metal ones that are also pricey.

 

[jimi]

Thanks guys the speaker switcher seems a really neat solution and I think I'll try it.

Actually have had an external speaker for a few years now but th jack plug's given up the ghost with repeated in & outs so wanted a better solution.

 

[BlueSkyNick]

I've got one of those speaker switch boxes on my hifi at home - I think you might find it a bit bulky on the boat.

 

[Colin_S]

Other problem with this device in a boaty envoironment is the fact that the wires are held in by sprung clamps and could easily be dislodged. After a lot of research (2 mins actually) I would go for a toggle switch of the SPDT variety (single pole double throw) and connect it to one of the speaker wires. If you want to make it a bit more involved, use a DPDT switch on both speaker wires. The wires can be soldered on and a better, permanent installation achieved.

SPDT internals

DPDT internal

 

[William_H]

Just to correct Robin with a 4 ohm source in the radio 2 by 8 ohm speakers in paralell gives 4 ohms true. However due to the desaign of modern audio output stages an 8 ohm load will not matter ie one speaker at a time or both on is OK. The very slight loss in power would be barely perceptible and will not damage the radio. (regardless of how high the load impedance.) unlike old valve amplifiers or transmitter output amplifiers. There may be some concern with low impedance speakers especially at high volume where amp could be overloaded. regards will

 

[alienzdive]

A second or backup VHF is a good idea too. One inside, one outside. No need then for wiring in new speakers!