BlueClone - The Blue Room's Own Comms System

[sunray]

I would put a fuse on the output of that psu... Save melting mic cables

Already in there (I think 1A) and 1.5 ohm resistor which sit between the original 2200uF and the 100uH. There's also a combined mains IEC/fuse/switch/filter and a LED/10K across the 24V o/p.

 

Did the show tonight and it was picking up very low level DMX, the bunch of cables running length of hall must have been dressed differently but otherwise perfect.

 

Next item to develop: remotely controlled switch to add comms into show relay. Should be easy, balanced I/p, simple mixer, balanced o/p and modified board letting the call function operate trigger a device like the mic switch does.

 

Edit: In fact now that lay in bed thinking about it, belt pack board has everything in place - Alter mic preamp to balanced line level I/p, let call cct trigger J175, remove cap between mic buffer and bus and move hybrid pot from I/p of mic buffer to o/p. h/p amp provides balanced o/p. The only question I can't answer from bed is 'will another XLR fit in place of the dip switch on the back panel'?

Edited May 6, 2018 by sunray

[pmiller056]

Does anyone have any experience or ideas on how to connect standard telephone equipment to a Blueclone-type system? (I do NOT want to connect Blueclone to the public telephone system!)

 

A bit of background.... Our community theatre finds it impractical to have a wired beltpack for all users. The backstage manager/stagehand/gofer/dogsbody has to be able to do things away from the beltpack location and will frequently forget to put the headphones back on when they return. We need a wireless system so that this person can do their job and be on the headphone system reasonably continuously. Two way radios are not appropriate in many locations backstage. I don't want to use bluetooth (there are commercial bluetooth interfaces available) or any 2.4/5GHz system because of potential interference from the multitude of mobile phones in audience pockets.

 

I'm thinking of using something based on a DECT cordless phone which natively does full duplex, unlike a two way radio based system. I'm happy to modify a phone handset to headphone use, taking into account possible microphone interface and battery lifetime/charging issues. What I'm getting stuck with is interfacing the cordless phone base station telephone line connection to the intercom system party line. Dialling and ringing are not relevant, and we can live without the intercom signal lamp function. I know I'll need to use an isolation transformer and some DC blocking capacitors, but I'm not sure about signal levels. I think there may have been some commercial telephone interfaces available for similar systems in the past, but I've drawn a blank for model numbers, never mind the internal workings of them.

 

Any ideas anyone?

 

Thanks,

 

Peter

[dmxlights]

Hi Peter,

 

I have been thinking of something like this. I do know if you hve 2 fixed phone and put a battery between them you can hear use them as a intercom but the phone will not ring. I maybe able to do some experments over this weekend and see if I can interface them with bluecoms or another coms system.

 

I will post back my finding here if it is do able or not.

[henny]

Hi Peter,

 

I have been thinking of something like this. I do know if you hve 2 fixed phone and put a battery between them you can hear use them as a intercom but the phone will not ring. I maybe able to do some experments over this weekend and see if I can interface them with bluecoms or another coms system.

 

I will post back my finding here if it is do able or not.

 

 

connect a phone across pins 1 & 3 on a coms line and you may be surprised what happens when the call button is pressed on a belt pack, then take a Dect phone that doesn't need power from the line

[sunray]

I have been thinking along the same lines but wanted to test it before posting.

 

I fully expect a Dect phone to require the DC element across the line for internal signalling.

 

I was planning to try with a transformer 477 and use the BlueCom 24V power with some current limiting to energise the phone line.

 

My big concern: some (possibly cheap) Dect phones have a tendency to feed the I/C audio back out at a low level with a small delay which may be too noticeable on headphones.

 

Personally I'd look at using full duplex radios, it's well proven and non digital so less prone to falling over.

Edited May 10, 2018 by sunray

[jmvbmw]

.

.

.

Do this device, the same work?

 

http://www.radialeng...ecube-specs.php

 

No, the schematic shows that it doesn't have a centre tapped transformer nor an isolating capacitor. However, if you don't need to supply power to the Telex system from the Bluecom system it would be easy enough to just add the capacitor yourself.

 

 

Hi John and forum friends!

 

Back again with Telex compatibility

 

This device, will do the work?

 

http://www.rtsintercoms.com/us/rts/product/CCB-1/1304

 

Cheers!!

 

 

 

[boatman]

 

Hi John and forum friends!

 

Back again with Telex compatibility

 

This device, will do the work?

 

http://www.rtsintercoms.com/us/rts/product/CCB-1/1304

 

Cheers!!

 

There's no schematic in the technical documentation so I can't be sure but I think it probably will.

[jmvbmw]

Hi John and forum friends!

 

Back again with Telex compatibility

 

This device, will do the work?

 

http://www.rtsinterc...duct/CCB-1/1304

 

Cheers!!

 

There's no schematic in the technical documentation so I can't be sure but I think it probably will.

 

Confirmed, the Telex CCB-1 "Balanced Audiocom to Unbalanced Clear-Com" box that I mentioned in my last post, does work very well.

Now, I can use a Telex intercom and our bluecom's together in the same line

Edited August 16, 2018 by jmvbmw

[skinda0]

I have been building up a 'master station' for use with the beltpacks and have now reached a point where I can start some initial tests with a few belt packs connected.

I designed the master station to hold all of the power supply circuitry as well as the termination circuitry. I have also added a line input module so auxiliary inputs can be put on the comms bus. The master station is also a dual channel unit that can be switched to connect bus A and B. This is all working as planned! I have also used a spare beltpack PCB inside the master station so I have a headset connection available.

 

During my initial tests, I have noticed that the 'thump' in the headphones when the call button is pressed seems to be a lot louder than I expected. Is there a way to reduce this or have I got something wrong? I thought there was a thump as a bi-product of the call circuitry but I didn't expect it to be as loud as it is.

[jmvbmw]

I have been building up a 'master station' for use with the beltpacks and have now reached a point where I can start some initial tests with a few belt packs connected.

I designed the master station to hold all of the power supply circuitry as well as the termination circuitry. I have also added a line input module so auxiliary inputs can be put on the comms bus. The master station is also a dual channel unit that can be switched to connect bus A and B. This is all working as planned! I have also used a spare beltpack PCB inside the master station so I have a headset connection available.

 

During my initial tests, I have noticed that the 'thump' in the headphones when the call button is pressed seems to be a lot louder than I expected. Is there a way to reduce this or have I got something wrong? I thought there was a thump as a bi-product of the call circuitry but I didn't expect it to be as loud as it is.

 

I did the same 'thump' in my system. Some beltpacks louder than others... never fixed it at all, but the set run solid as a rock since 2015

Check for a missing termination of the audio line

Edited August 29, 2018 by jmvbmw

[kgallen]

I have noticed that the 'thump' in the headphones when the call button is pressed seems to be a lot louder than I expected.

 

Same for me on all 4 beltpacks I've built. I'd be interested if there is a way to reduce the thump - both for my hearing and for the survival of the headphones! If I interconnect with a Tecpro beltpack, the Tecpro thump is quiet and the Bluecom is loud, so it seems to be specific to the Bluecom circuit.

 

Kevin

 

 

 

[skinda0]

I'd be interested if there is a way to reduce the thump - both for my hearing and for the survival of the headphones!

 

I have a few pairs of these superlux headsets and the thump is quite painfull! I also have a few pairs of Beyerdynamic DT109s and the thump is nowhere near as painful, in fact it is quite a deep 'boof' rather than the superlux headsets which are much more like a loud click!

[boatman]

Unfortunately I'm not able to do any testing just now but if someone could try changing C22 from 100nF to either 1uF (or even 10uF) that might solve the "thump" problem.

[jmvbmw]

John, Thank you, again , for all your efforts

 

Unfortunately, changing the c22 for a 10nF one (same as c2) make no difference for me

 

Best regards

[skinda0]

Unfortunately, changing the c22 for a 10nF one (same as c2) make no difference for me

 

10nF? Should be 10uF. You could try a 1uF which are already used as C17/C18 if you have some spare.