BlueClone - The Blue Room's Own Comms System

[skinda0]

Cheaper than building one? https://rover.ebay.c...%2F123415221980

 

I could purchase one, but I have a load of spare beltpack pcbs that I need a use for, and I like to make stuff! http://www.blue-room.org.uk/public/style_emoticons/default/biggrin.gif

 

 

[sunray]

I have found I need to adjust the sidetone pots almost everytime I use the bluecom sets and had assumed it's due to the number of units in use, until today while setting up for a show next week I set up the same 4 beltpacks as last time.

The difference is the PSU used, last time I used my homemade unit and today the 721.

I substituted the homemade and they returned to 'tuned' state. I adjusted them for the 721 as I wanted the aux in facility, out of curiosity I then tried te other channel of the 721 and again out of balance.

Has anyone else noticed this?

Edited February 12, 2019 by sunray

[boatman]

It's nothing to do with Bluecom but differing resistor values in audio line terminations. You'll get the same effect when adding or removing beltpacks from a system. Luckily it's very easy to adjust the sidetone on Bluecom beltpacks.

[sunray]

It's nothing to do with Bluecom but differing resistor values in audio line terminations. You'll get the same effect when adding or removing beltpacks from a system. Luckily it's very easy to adjust the sidetone on Bluecom beltpacks.

My observation has eventually found it is dependant on which PSU I use the bluecoms on rather than quantity or which even channel I use on the 721. Generally I find removing beltpacks from a system makes very little difference.

The reason I ask is one guy I work with has a decent supply of BP1's and several PSU's and I don't recall ever having to tweek them regardless of how many packs are used.

Edited February 12, 2019 by sunray

[Brian]

It's nothing to do with Bluecom but differing resistor values in audio line terminations. You'll get the same effect when adding or removing beltpacks from a system. Luckily it's very easy to adjust the sidetone on Bluecom beltpacks.

My observation has eventually found it is dependant on which PSU I use the bluecoms on rather than quantity...

 

Comms power supplies have, or rather should have, termination resistances in them for the audio line. Something like a 470R resistor in series with a 10k resistor, with the 10k bypassed by a 10uF capacitor seems quite common.

[kgallen]

Something like a 470R resistor in series with a 10k resistor, with the 10k bypassed by a 10uF capacitor seems quite common.

 

Quoted many times before on BR I believe (and probably several of them by Brian!), so in schematic form:

 

https://www.blue-room.org.uk/index.php?showtopic=46249&view=findpost&p=383498

 

http://www.dmx512.co...cpro/tptech.htm

Edited February 13, 2019 by kgallen

[sunray]

Thanks for the replies. I set up a 721 yesterday with 2 bluecomms and inadvertently used the other channel from the night before so the side tone was wrong. A quick re-plug soon fixed it but it has more use with techpro packs and I'm convinced they are less sensitive to the issue.

 

Hopefully I'll be able to have a real play in a few weeks.

Edited February 16, 2019 by sunray

[sunray]

Thanks for the replies. I set up a 721 yesterday with 2 bluecomms and inadvertently used the other channel from the night before so the side tone was wrong. A quick re-plug soon fixed it but it has more use with techpro packs and I'm convinced they are less sensitive to the issue.Hopefully I'll be able to have a real play in a few weeks.

 

During rip out today I managed to have a little play in a 'real world' environment, the system in use last night was 3 bluecom belt packs, one on the end of about 30m of FST from the 721 and the 2nd on a 20m mic cable then 6m link to the 3rd. All nicely zero'd on circuit 'A'.

Moved the beltpacks to the location of the 721 by adding 2 20m mic cables which made no difference.

Changing to circuit 'B' meant all 3 packs had obviously more side tone and loads with my home made PSU. Each time I could easily re-zero them.

 

I repeated with 2 BP1's and a BP2, zero'd them on circuit 'A' then moved to 'B' with no apparent change.

On my home made PSU there was just a little more side tone.

 

Exactly the same results happened with a second 721.

 

From this, my conclusion is the bluecom's are more sensitive to variations than Techpro.

 

This is observation/feedback, not critisism.

Edited February 17, 2019 by sunray

[jmvbmw]

Thanks for the replies. I set up a 721 yesterday with 2 bluecomms and inadvertently used the other channel from the night before so the side tone was wrong. A quick re-plug soon fixed it but it has more use with techpro packs and I'm convinced they are less sensitive to the issue.Hopefully I'll be able to have a real play in a few weeks.

 

During rip out today I managed to have a little play in a 'real world' environment, the system in use last night was 3 bluecom belt packs, one on the end of about 30m of FST from the 721 and the 2nd on a 20m mic cable then 6m link to the 3rd. All nicely zero'd on circuit 'A'.

Moved the beltpacks to the location of the 721 by adding 2 20m mic cables which made no difference.

Changing to circuit 'B' meant all 3 packs had obviously more side tone and loads with my home made PSU. Each time I could easily re-zero them.

 

I repeated with 2 BP1's and a BP2, zero'd them on circuit 'A' then moved to 'B' with no apparent change.

On my home made PSU there was just a little more side tone.

 

Exactly the same results happened with a second 721.

 

From this, my conclusion is the bluecom's are more sensitive to variations than Techpro.

 

This is observation/feedback, not critisism.

 

 

I'm really didn't understand what is you problem, but let me tell you that I made my Bluecom's following both beltpacks and psu schematics.

I has been using my bluecoms in the last 3 years, in different "real world" indoor and outdoor conditions, in "real world" productions, even with 50 or 60m wires, and I've had zero problems or faults. Zero. The system is solid as rock

 

 

 

Having said that, a quick question: is this system compatible with our comm's?

 

https://fccid.io/BYMBH80074/User-Manual/manual-221208.pdf

 

 

Best regards!

[sunray]

Thanks for the replies. I set up a 721 yesterday with 2 bluecomms and inadvertently used the other channel from the night before so the side tone was wrong. A quick re-plug soon fixed it but it has more use with techpro packs and I'm convinced they are less sensitive to the issue.Hopefully I'll be able to have a real play in a few weeks.

 

During rip out today I managed to have a little play in a 'real world' environment, the system in use last night was 3 bluecom belt packs, one on the end of about 30m of FST from the 721 and the 2nd on a 20m mic cable then 6m link to the 3rd. All nicely zero'd on circuit 'A'.

Moved the beltpacks to the location of the 721 by adding 2 20m mic cables which made no difference.

Changing to circuit 'B' meant all 3 packs had obviously more side tone and loads with my home made PSU. Each time I could easily re-zero them.

 

I repeated with 2 BP1's and a BP2, zero'd them on circuit 'A' then moved to 'B' with no apparent change.

On my home made PSU there was just a little more side tone.

 

Exactly the same results happened with a second 721.

 

From this, my conclusion is the bluecom's are more sensitive to variations than Techpro.

 

This is observation/feedback, not critisism.

 

 

I'm really didn't understand what is you problem, but let me tell you that I made my Bluecom's following both beltpacks and psu schematics.

I has been using my bluecoms in the last 3 years, in different "real world" indoor and outdoor conditions, in "real world" productions, even with 50 or 60m wires, and I've had zero problems or faults. Zero. The system is solid as rock

 

 

 

Having said that, a quick question: is this system compatible with our comm's?

 

https://fccid.io/BYMBH80074/User-Manual/manual-221208.pdf

 

 

Best regards!

Don't get me wrong, once installed and adjusted they are fine.

My comments are observations that I find I have to adjust the sidetone If any sort of change takes place (but strangely adding or removing a station is ok) I don't have to adjust Tecpro Pack's on anything like the same regularity.

 

Normally I get to work on intercom systems about 6times a year but this last 2 weeks has been crazy for me, having installed 4systems (2 bluecom & 2 Tecpro). Both Tecpro went in without the use of any tools but every bluecom had to be adjusted on both jobs. The last had to go in Friday and Saturday as hall was in use for something else during day. I managed to use circuit A one day and B the other which would have meant adjusting 3 Pack's (easier to move 2 plugs) but trying the same setup with the same 721 (and another 721) with Tecpro packs I didn't have to adjust packs at all on the 4 PSU circuits.

 

Having done so much in a short time (for me) the difference between the two products was very noticeable.

 

3of us have made 6packs between us but sofar only one psu and Generally have not found the need to adjust when used on the one psu. The 721 was used as we needed to inject another signal.

[jmvbmw]

I own clear-com CC-60 and Telex PH-1 headsets, and I've only adjusted the sidetone once, the first time...

I have used the bluecoms in combination with tecpro and RTS telex (with CCB-1 interface), and no problems at all...

Edited February 19, 2019 by jmvbmw

[Brian]

My comments are observations that I find I have to adjust the sidetone If any sort of change takes place (but strangely adding or removing a station is ok) I don't have to adjust Tecpro Pack's on anything like the same regularity.

 

Could you clarify which changes affect things? You say adding a station (beltpack?) is OK so I assume you mean changing the power supply, and/or cabling, and/or system configuration.

[sunray]

My comments are observations that I find I have to adjust the sidetone If any sort of change takes place (but strangely adding or removing a station is ok) I don't have to adjust Tecpro Pack's on anything like the same regularity.

 

Could you clarify which changes affect things? You say adding a station (beltpack?) is OK so I assume you mean changing the power supply, and/or cabling, and/or system configuration.

I made a PSU and adjusted all 6 bluecom packs to work on it. I believe it makes no difference how many packs are used or how much cable. We now have a couple of 721 Tecpro and access to 2 more plus 2 other Techpro 3 channel PSU's. I find that I have to adjust the bluecom sidetone whenever I use them on a different PSU or PSU circuit. I'm seriously considering altering the PSU's to make them consistent.

I find it's quite rare to have to adjust techpro packs.

[Brian]

I don't have the schematics for a 721 here. Would you be willing to pop the lid and see what values of R and C they have in the termination networks. It a pair of series connected resistors, one around 200-500 Ohms, the other in the 4k7 to 10k range. The larger value has one end to ground and is bypassed by a capacitor of around 10uF.

 

You can compare with the BlueCom one documented here...

 

https://www.blue-room.org.uk/index.php?showtopic=59644&view=findpost&p=486728

 

When John and I designed BlueCom we looked at what everyone else did and found quite a wide variation in things like the audio level on the line and termination networks so ended up picking a middle set of values so that it should work with most systems.

[J Pearce]

It's not unknown for the termination networks in older Tecpro units to fail, or at least drift out of specification. Perhaps this is the cause of your issues?