BlueClone - The Blue Room's Own Comms System

[pedromigcruz]

I have had a quick look at your pic of the board there looks to be a few solder joints that may need doing again but I could be wrong.

 

I have ringed them in red.

 

When I work with double sided boards I always make sure it well sorldered as in it come out the other side as well.

http://mcgcs.net/pics/pack.jpg

Although it seems like a bad solder, there is continuity in between lower pad and upper pad because the holes are Pre tinned from factory.

 

Thanks for your help and patience.

At this point 5 beltpacks are confirmed to suffer from the same symptom, it can be because I’m supplying 12v to the psu instead of 24v, but I’m not sure why I also get the same problems once I connect it to an Altair or ASL base station

Edited April 20, 2019 by pedromigcruz

[NickNickNick]

I wouldn't recommend anything less than 32 ohms. Lower impedances will work but will draw a significant current from the power supply and might destroy the protection resistors R16 & R20.

 

The standard headphones for comms systems are 400 ohms.

 

Ah right, I thought that would be the case. I am looking at building a little desktop base station with a speaker and built in mic. I wondered if the headphone amp would do to drive a little high impeadence speaker. Ill stick a little amplifier in there then to drive it.

 

Hi there,

I'm just wondering how you got on with this project? I'm searching the net, looking to build exactly what you're talking about (desk top speaker station) to go with an existing JANDS Ezicom system (works on the same system as ClearCom) and this product looks like an interesting way to do it. Would putting a 390 Ohm wire wound resistor in line with the speaker make it work?

Thanks!

Edited July 3, 2019 by NickNickNick

[Brian]

Would putting a 390 Ohm wire wound resistor in line with the speaker make it work?

 

No.

 

If you put a 390R resistor in series with an 8R speaker the resistor will drop too much voltage and hence too little power will be developed in the speaker.

 

High impedance speakers are available, a quick look online finds plenty of 64R parts which area better match to the unit.

 

An even better way is to buy a small amplifier module from eBay and use that to drive the speaker.

 

Note however that the amount of current you draw from the PSU goes up a lot as you drive more power into the speaker. It is probably better to make a desktop unit with its own local power supply.

[skinda0]

Would putting a 390 Ohm wire wound resistor in line with the speaker make it work?

An even better way is to buy a small amplifier module from eBay and use that to drive the speaker.

 

Note however that the amount of current you draw from the PSU goes up a lot as you drive more power into the speaker. It is probably better to make a desktop unit with its own local power supply.

 

That is exactly what I did.

I used a beltppack PCB and didn't fit the headphone amplifier section. I took the input to the headphone amplifier, via a pot to adjust the volume, to a small 3W 8R speaker amplifier module.

This was powered from an external power supply to reduce the current drawn over the coms line. Coms line only powered the beltpack PCB.

[dmxlights]

I am hopping someone here will have some spare end panels for the beltpacks. I have loss 2 as I was doing an experment with 2 would like to replace them. On the other hand if anyone has 3 end panels spair and also a beltpack pcb or 2. I would be happy to take them off them.

 

[sunray]

I certainly have the PCB's available but I think all of the front and back panels have now gone, hopefully I'll be in a position to check mid week. Please send reminders

I am hopping someone here will have some spare end panels for the beltpacks. I have loss 2 as I was doing an experment with 2 would like to replace them. On the other hand if anyone has 3 end panels spair and also a beltpack pcb or 2. I would be happy to take them off them.

 

[dmxlights]

Thank you for your reply and will endeed send you a reminder.

 

I certainly have the PCB's available but I think all of the front and back panels have now gone, hopefully I'll be in a position to check mid week. Please send reminders

I am hopping someone here will have some spare end panels for the beltpacks. I have loss 2 as I was doing an experment with 2 would like to replace them. On the other hand if anyone has 3 end panels spair and also a beltpack pcb or 2. I would be happy to take them off them.

 

[Peaveydisco]

Just thought I'd add a quick comment to say I've built a number of these units over the past few months for an amateur group. They had their first outing last week, used in a commercial theatre along runs of 50m plus, and they worked brilliantly B-)

 

There appeared to be some slight distortion on one headset, but nothing that wasn't bearable, anyone come across such an issue?

 

They're certainly a million times better that the 446 radio's we've used in the past! Time to build some more, and perhaps even a 19" rack mount version for the sound guy

Edited November 8, 2019 by Peaveydisco

[boatman]

.

.

There appeared to be some slight distortion on one headset, but nothing that wasn't bearable, anyone come across such an issue?

.

.

 

Did you try swapping the headsets around to see if it's the headset or the beltpack?

[Filmmaker75]

Hello everyone! I built two beltpacks and the PSU. All works but there is a strong background noise in the headphones. Hum. If I place a finger on the PSU's capacitors the buzz disappears. If I touch the metal of the potentiometer of the volume instead it increases a lot. I haven't put the PCBs in the boxes yet and I'm trying them on the desk.

I'm using a PC headset. I measured with the tester the headphone output has about 9v ... By removing the headphones the voltage reaches 11v

Any suggestions?

Edited November 15, 2019 by Filmmaker75

[pmiller056]

I had similar problems when using a double-insulated brick-in-the-wall type power supply. The cure was to *only at one point in the system* connect power supply negative/cable screen to mains earth. There are various ways of accomplishing this depending on how competent you are at making mains powered electrical things.

[Brian]

^^^That.

 

The audio is run unbalanced and so you need an earth connection at one point, and only at one point, somewhere in the system. And the usual place to do that is the power supply. Using a wall-wart with no proper earth connection is not recommended.

[Filmmaker75]

I had similar problems when using a double-insulated brick-in-the-wall type power supply. The cure was to *only at one point in the system* connect power supply negative/cable screen to mains earth. There are various ways of accomplishing this depending on how competent you are at making mains powered electrical things.

 

^^^That.

 

The audio is run unbalanced and so you need an earth connection at one point, and only at one point, somewhere in the system. And the usual place to do that is the power supply. Using a wall-wart with no proper earth connection is not recommended.

 

Thanks for the reply. I'm using this power supply to test the system:

 

http://www.minoiailluminazione.com/16439-22636-large/arteleta-lb437-alimentatore-24v-100w.jpg

 

Do I have to connect the -V with grounding?

 

I searched for other 24 volts power supplies, even for notebooks, but I didn't find power supplies with a three-pin plug. In the picture below it is clear that there is no earth connection.

 

I also have another question. I'm using a PC headset. I connected the microphone to the MIC and GND terminals and the headset to HP + and GND and so it works. The headphone has an impedance of 32ohm and I noticed that the two resistances R16 and R20 will heat up a lot. To avoid damage I try to turn on the beltpack only a few minutes at a time. I purchased Superlux headphones for Intercom that have 150ohm impedance that will arrive next week. Will they get better?

 

Sorry for the long post but I'm not very experienced. I just bought the components and soldered them, I'm not very expert in electronics. Thanks for your help.

Edited November 16, 2019 by Filmmaker75

[sunray]

 

I also have another question. I'm using a PC headset. I connected the microphone to the MIC and GND terminals and the headset to HP + and GND and so it works. The headphone has an impedance of 32ohm and I noticed that the two resistances R16 and R20 will heat up a lot. To avoid damage I try to turn on the beltpack only a few minutes at a time. I purchased Superlux headphones for Intercom that have 150ohm impedance that will arrive next week. Will they get better?

 

Sorry for the long post but I'm not very experienced. I just bought the components and soldered them, I'm not very expert in electronics. Thanks for your help.

Using HP+ and GND is wrong, that will overheat R20 but R16 should remain cold.

 

The headphones have to be connected between HP+ and HP-. They must NOT be connected to GND.

 

Are you using metal 3.5mm jack sockets? If you are, the HP socket has to be insulated from the earthed front panel.

[Filmmaker75]

I use a headset for PC that has a common ground between the headphones and the microphone.

 

I read that I don't have to connect HP- with GND.

 

I have to wait for the headphones I ordered to arrive, they have separate GND headphones and microphone.