Spectra to Whelen Siren

[KitN1MCC]

is there any concerns about hooking the Out put to the Blue Wires on the Whelen Siren

[alex]

is there any concerns about hooking the Out put to the Blue Wires on the Whelen Siren

Your trying to do what? I know you can put together a sentence... but jesus... how do you expect anyone to be able to help you if you can't accurately explain what you want help with!

Man oh man!

-Alex

[TWL911]

I'm thinking he is asking if anyone has experienced any issues with hooking up a spectra to a whelen siren to utilize the radio rebroadcast feature. At least I think thats what the blue wires do.

I think the whelen install sheets specify that you tap the blue wires to each of the remote speaker wires of your radio.

Sorry, I can't help more than that, I have never had a need for radio rebroadcast.

[thebigphish]

i know it's that easy with a CDM series install, but don't Spectra's have those cool unbalanced speaker leads?

And as for the sentences? It's ok Kitt, we all understand the state of affairs of the Middletown public schools! that or you can blame it on the water!

[Pj]

Spectra speaker to Whelen sirens are just fine.

just tap the whelen wires in line with the spectra. One blue wire to each side (not inline).

[Pj]

Lemme clarify... if you shoved one blue wire into one side of the plug, and the other blue wire on the other side, your good to go... Just make sure you don't short both lines or the audio chip goes poof..

As Egon says...don't cross the streams!

The whelen diagram looks like you splice into the line on both ends, but thats not the case.

[jackhackett]

i know it's that easy with a CDM series install, but don't Spectra's have those cool unbalanced speaker leads?

No, Spectras have balanced speakers outputs, as do CDMs.

Spectras seem to be especially picky, I've seen the RRB input on a Code3 siren, which has about 10K resistance to ground IIRC, shut down the audio on one... doesn't take much.

If you want to be safe connecting a radio to siren RRB you can use a 600:600 ohm audio transformer between them, one side to the speaker leads, other to the RRB input. For a couple of bucks and a little extra wiring work it's cheap insurance, and even if you didn't need it, putting one in shouldn't hurt anything.

Just be sure you don't leave the transformer leads exposed where they can touch anything... I solder some hookup wire to them and then give the whole thing a real good wrapping of electrical tape.

[dbcomm]

i know it's that easy with a CDM series install, but don't Spectra's have those cool unbalanced speaker leads?

No, Spectras have balanced speakers outputs, as do CDMs.

Spectras seem to be especially picky, I've seen the RRB input on a Code3 siren, which has about 10K resistance to ground IIRC, shut down the audio on one... doesn't take much.

If you want to be safe connecting a radio to siren RRB you can use a 600:600 ohm audio transformer between them, one side to the speaker leads, other to the RRB input. For a couple of bucks and a little extra wiring work it's cheap insurance, and even if you didn't need it, putting one in shouldn't hurt anything.

Just be sure you don't leave the transformer leads exposed where they can touch anything... I solder some hookup wire to them and then give the whole thing a real good wrapping of electrical tape.

I'll have to find a link, but I use these little 600:600 jobbers that are fully encapsulated, and just have 6" leads that I solder to the rrb/speaker leads. I just put some heat shrink over the solder connx's and don't have to worry about the txfrmr shorting. It also has a spot for a single mounting screw should it be neccesary.

[jackhackett]

I'll have to find a link, but I use these little 600:600 jobbers that are fully encapsulated....

Nice. I'd be interested in some of those.

[mr.syntrx]

In the past, I've bought some small potted housings with screw flanges, soldered leads to the transformer, dropped the transformer in the housing, and filled the housing with epoxy or silicone.

[KitN1MCC]

is there any concerns about hooking the Out put to the Blue Wires on the Whelen Siren

Your trying to do what? I know you can put together a sentence... but jesus... how do you expect anyone to be able to help you if you can't accurately explain what you want help with!

Man oh man!

-Alex

i was in a Hurry sorry. Seems like i am Not Very Welcomed on here.

[KG4RZU]

Kit, sorry to see another throat has been cut by administrators and moderators that do not want to encourage the knowledge, and hands-on training of the technicians and engineers of our future.
Some people like myself, try to ask a question that we may not be able to phrase in a statement that technicians that have many, many years of experience might not care to understand.
Seems that you were getting on Alex's nerves or bothering him by your trying to promote understanding of a fast and vastly changing technical field.
Instead you were blasted by Alex, and I'm sure I probably will be also..
This board in the last few years has pushed away many of the best electronic techs that I read posts about.
DON'T GET DISCOURAGED!
There are people out here to help instead of wanting to ridicule because they have some authority.
Alex, Sorry nobody is as smart as you..
Are you a moderator or authority??

I do not claim to know everything I need to know about electronics,but you will never be on my list to ask for help.
Hang in there Kit, there are brother techs out there willing to help those that are still training.
Sorry I don't see many here.
KG4RZU

[alex]

Kit - your welcome here - you know that. But you need to put your posts together so that they make sense. I've met you countless number of times and know you can do it! I know we've talked about it in the past - but if you need help, you need to make sure that you explain the problem. Your sentence didn't make much sense - and it was an effort to try and get you to elaborate! You should know that with the amount of times you've met up with this group!

KG4RZU -

I don't even know what to say to your post. It's probably one of the stupidest posts that I've read here in a while. Carefully crafted by someone who obviously doesn't understand the situation. Have you met Kit? You'd know that he's a very smart, young man, who has some good knoledge on a lot of stuff - but knows he doesn't craft his messages here as well as he could. He's said that himself over dinner at Friday's in Middletown - there were 10 other people there.

Before you go and comment on a situation you don't understand or know nothing about - you might want to think twice.

-Alex

[Pj]

Are you a moderator or authority??

alex
Administrator


Joined: 03 Sep 2001
Posts: 4200

I was at that dinner myself. Kit has in the past put together really good posts. I don't know if he is just always in a rush or what, but some posts are difficult to translate at times. He often does get a ribbing on here and at Hamsexy. All I can say is to ask Kit to slow down on the keyboard and have fun...

[JAYMZ]

So what's the solution? Tap directly into the speaker leads from the Spectra? Or is a transformer needed? I wouldn't mind having radio rebroadcast again.

[jmr061]

Back in the day before I was totally into M stuff I took the speaker leads and just tapped into them for radio re-broadcast through a PA300, just make sure you don't short or ground them out during install, I would disconnect the speaker, tap into them and the re-hook up the speaker. Should be good to go then.

Jason

[tvsjr]

Or build up a male-female passthrough using the typical Spectra speaker connectors, with an output off to the siren.

[TWL911]

slightly off topic:

what about tapping audio from an MCS2000 speaker?
I have never used Radio rebroadcast before, but I'm in the process of installing a new console and now that the MCS head will be right next to the HFS4 I may try it, "just because I can" If I can.

[jackhackett]

So what's the solution? Tap directly into the speaker leads from the Spectra? Or is a transformer needed? I wouldn't mind having radio rebroadcast again.

It depends on the siren, some have a transformer built in, some have blocking caps, some have a resistor to ground.. you'd have to know what the RRB input circuit is like on the siren you're using.

As I said, if you want to play it safe use a transformer, then it won't matter what's in the siren.

As for the MCS2000, same thing goes. Pretty much any of the later mobiles use the balanced speaker outputs.

[kj7xe]

All of the LE vehicles here are installed with enabling the radio re-broadcast feature, most of which are WS295HFSA5 units connected to front-mount XTL-5000s and analog Spectras. We connect the blue leads in paralell with the radio's speaker leads (in accordance with the installation instructions) and never had any trouble that I know of.

Looking at the schematic for the Whelen WS295 series siren box it appears that the blue leads already go through an isolation transformer (to convert between balanced [radio] and unbalanced [siren]), a 680 ohm resistor in series, and 1k pot in paralell (to adjust the volume) all on the balanced side. So it appears to me that an additional transformer would not be needed since it's already there.

As I recall, the MCS2000 freaks out when you short either lead to ground - I know the Spectra will draw a whole bunch of current before the audio PA goes poof... hehe

[KitN1MCC]

i was just wondering due to the Big tag on the Speaker Leads. i dont wanna blow up the radio

[kj7xe]

i was just wondering due to the Big tag on the Speaker Leads. i dont wanna blow up the radio

I can definately understand. What make/model of siren box are you using?

[JAYMZ]

I am using a MPC01 Serial Control setup... think that would make a difference hooking to an Astro Spectra? I really don't want to have to replace the audio IC, or Command Board from this radio.

[kj7xe]

I am using a MPC01 Serial Control setup... think that would make a difference hooking to an Astro Spectra? I really don't want to have to replace the audio IC, or Command Board from this radio.

No difference, the B-Link system is very similar. If you connect to the blue wires (pins 6 & 7 on J8 power connector) off the MPC control head in paralell with the speaker leads of the Spectra, adjust the RRB pot (on the back of the control head) for best volume, then you're set to go.

Basically, the radio wants to see a low speaker impedance/resistance is (8 or less ohms in most cases, all the way down to 2 ohms on the MCX1000) and all of the siren boxes i've seen with this feature tap off the speaker leads with a higher resistance (usually at least 600 ohms) so no harm should be done to the radio. It's when you drop below the radio's rated impedance/resistance that you have problems.