Using a 6" length of 28 AWG IDC10 cable for audio hookup?

[Don Kuenz]

Is it feasible to use a 6" length of 28 AWG IDC10 cable to hookup a
front panel to an audio PCB? The front panel contains: input and output
stereo jacks, a volume control potentiometer, and a 12 VDC 1A power
input jack.

Thank you in advance, 73,

--
Don Kuenz KB7RPU
There was a young lady named Bright Whose speed was far faster than light;
She set out one day In a relative way And returned on the previous night.

 

[John Robertson]

On 2019/06/28 10:24 a.m., Don Kuenz wrote:

Is it feasible to use a 6" length of 28 AWG IDC10 cable to hookup a
front panel to an audio PCB? The front panel contains: input and output
stereo jacks, a volume control potentiometer, and a 12 VDC 1A power
input jack.

Thank you in advance, 73,

I would say only if the conductors are shielded or twisted pairs. 6
inches is not very long (15cm for everyone else) and if in a metal
cabinet and well shielded power supply should be OK, but I'd still want
twisted pairs for signal lines.

John :-#)#

 

[Rick C]

On Friday, June 28, 2019 at 1:24:54 PM UTC-4, Don Kuenz wrote:

Is it feasible to use a 6" length of 28 AWG IDC10 cable to hookup a
front panel to an audio PCB? The front panel contains: input and output
stereo jacks, a volume control potentiometer, and a 12 VDC 1A power
input jack.

I would put a ground wire between each signal lead to minimize crosstalk, but otherwise it shouldn't be an issue. So 10 wire may not be enough.

Not sure 28 gauge is enough for 1 amp of current. That wire will be pretty warm. Use two and it won't be a problem.

So 2 power, 3 ground, 4 input/output and whatever you need for the potentiometer which may also need isolating grounds.

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

 

[bitrex]

On 6/28/19 1:49 PM, John Robertson wrote:

On 2019/06/28 10:24 a.m., Don Kuenz wrote:
Is it feasible to use a 6" length of 28 AWG IDC10 cable to hookup a
front panel to an audio PCB? The front panel contains: input and output
stereo jacks, a volume control potentiometer, and a 12 VDC 1A power
input jack.

Thank you in advance, 73,


I would say only if the conductors are shielded or twisted pairs. 6
inches is not very long (15cm for everyone else) and if in a metal
cabinet and well shielded power supply should be OK, but I'd still want
twisted pairs for signal lines.

John :-#)#

I've seen line-level signals to and from front panels sent over runs of
a foot or more of just zip-tied random wire bundles connected to the PCB
with plastic female headers into male terminal header pins; it might not
be "best practices" but it's cheap and seems to work well enough for
rock-and-roll. a hundred million pieces of prosumer "kit" have been
built that way.

 

[bitrex]

On 6/28/19 1:24 PM, Don Kuenz wrote:

Is it feasible to use a 6" length of 28 AWG IDC10 cable to hookup a
front panel to an audio PCB? The front panel contains: input and output
stereo jacks, a volume control potentiometer, and a 12 VDC 1A power
input jack.

Thank you in advance, 73,

The power input jack is on the front of the enclosure? kinda odd.

I might feel OK putting local regulated/well-filtered DC bus voltages in
an IDC cable next to line-level signal but not the main PSU input from
the $5 switching wall-wart with 200mV of dreck riding on it, no.

 

[bitrex]

On 6/29/19 2:43 AM, bitrex wrote:

On 6/28/19 1:49 PM, John Robertson wrote:
On 2019/06/28 10:24 a.m., Don Kuenz wrote:
Is it feasible to use a 6" length of 28 AWG IDC10 cable to hookup a
front panel to an audio PCB? The front panel contains: input and output
stereo jacks, a volume control potentiometer, and a 12 VDC 1A power
input jack.

Thank you in advance, 73,


I would say only if the conductors are shielded or twisted pairs. 6
inches is not very long (15cm for everyone else) and if in a metal
cabinet and well shielded power supply should be OK, but I'd still
want twisted pairs for signal lines.

John :-#)#

I've seen line-level signals to and from front panels sent over runs of
a foot or more of just zip-tied random wire bundles connected to the PCB
with plastic female headers into male terminal header pins

To be correct in terms I mean plastic female connectors into male
box-headers.

 

On Saturday, 29 June 2019 07:43:26 UTC+1, bitrex wrote:

On 6/28/19 1:49 PM, John Robertson wrote:
On 2019/06/28 10:24 a.m., Don Kuenz wrote:
Is it feasible to use a 6" length of 28 AWG IDC10 cable to hookup a
front panel to an audio PCB? The front panel contains: input and output
stereo jacks, a volume control potentiometer, and a 12 VDC 1A power
input jack.

Thank you in advance, 73,


I would say only if the conductors are shielded or twisted pairs. 6
inches is not very long (15cm for everyone else) and if in a metal
cabinet and well shielded power supply should be OK, but I'd still want
twisted pairs for signal lines.

John :-#)#

I've seen line-level signals to and from front panels sent over runs of
a foot or more of just zip-tied random wire bundles connected to the PCB
with plastic female headers into male terminal header pins; it might not
be "best practices" but it's cheap and seems to work well enough for
rock-and-roll. a hundred million pieces of prosumer "kit" have been
built that way.

keep the impedance down or make the inout differential & you can get away with it over fairly long distances.


NT

 

[Don Kuenz]

John Robertson <spam@flippers.com> wrote:

On 2019/06/28 10:24 a.m., Don Kuenz wrote:
Is it feasible to use a 6" length of 28 AWG IDC10 cable to hookup a
front panel to an audio PCB? The front panel contains: input and output
stereo jacks, a volume control potentiometer, and a 12 VDC 1A power
input jack.

I would say only if the conductors are shielded or twisted pairs. 6
inches is not very long (15cm for everyone else) and if in a metal
cabinet and well shielded power supply should be OK, but I'd still want
twisted pairs for signal lines.

Thank you everyone for more-or-less confirming my suspicions that using
unshielded 28 AWG ribbon cable as audio and power hookup wire is a poor
choice for this case, a 2 3/4" X 4" Bud box literally and figuratively
crammed full of components.

Rick C, the 12 VDC 1A wall wart output is a worst case scenario. The
circuit theoretically ought to draw no more than a few hundred
milliamps. But that's too darned close to the 28 AWG wire's 228 milliamp
current carrying capacity at 700 circular mils per amp.

bitrex, you may refer to Intel's AC97 standard. Although it's a step in
the right direction its 9 pin IDC header is too limiting for this
particular project.

John's twisted idea works best. It inspired me to solder like a mad man
last night.
The whole point behind my now discarded ribbon cable scheme was to
1) avoid a tangle of hookup wire and 2) enable easy disconnection.
Twisted wire is a great compromise that achieves both goals /and/ cuts
the hookup length down to a mere 3".
A triple twist is used for stereo signals. It looks like this:
http://mid-8704.kxcdn.com/wp-content/uploads/2016/03/D-B-R-Y-TW-WIRE-22AWG-TWISTED-TRIPLE-BLACK-RED-YELLOW-L.jpg
Plain vanilla twisted pair is used for the power connection. The PCB end
of the hookup bundles are inserted into SIP sockets, which provide the
easy disconnect:
https://www.taydaelectronics.com/media/catalog/product/cache/1/image/500x500/9df78eab33525d08d6e5fb8d27136e95/S/I/SIP_Socket_2_1.jpg

Allow me a small rant about the Cat 5 twisted pair solution that was
discarded along the way to my ultimate hand twisted 26 AWG wire
solution. Although the printed label on the outside of every piece of
Cat 5 twisted pair cable examined by me clearly states "24 AWG," in
actuality, it's 28 AWG every single time.

Thank you, 73,

--
Don Kuenz KB7RPU
There was a young lady named Bright Whose speed was far faster than light;
She set out one day In a relative way And returned on the previous night.

 

[bitrex]

On 6/29/19 9:24 AM, Don Kuenz wrote:

John Robertson <spam@flippers.com> wrote:
On 2019/06/28 10:24 a.m., Don Kuenz wrote:
Is it feasible to use a 6" length of 28 AWG IDC10 cable to hookup a
front panel to an audio PCB? The front panel contains: input and output
stereo jacks, a volume control potentiometer, and a 12 VDC 1A power
input jack.

I would say only if the conductors are shielded or twisted pairs. 6
inches is not very long (15cm for everyone else) and if in a metal
cabinet and well shielded power supply should be OK, but I'd still want
twisted pairs for signal lines.

Thank you everyone for more-or-less confirming my suspicions that using
unshielded 28 AWG ribbon cable as audio and power hookup wire is a poor
choice for this case, a 2 3/4" X 4" Bud box literally and figuratively
crammed full of components.

Rick C, the 12 VDC 1A wall wart output is a worst case scenario. The
circuit theoretically ought to draw no more than a few hundred
milliamps. But that's too darned close to the 28 AWG wire's 228 milliamp
current carrying capacity at 700 circular mils per amp.

bitrex, you may refer to Intel's AC97 standard. Although it's a step in
the right direction its 9 pin IDC header is too limiting for this
particular project.

??????

the +5V power connector on the AC97 header is fed from a well-regulated
and filtered rail for the audio codec circuitry on the mobo designed to
supply relatively small current for e.g. a front-panel mounted headphone
amp or status LEDs, they don't route the whole +5 system supply bus thru
that.

John's twisted idea works best. It inspired me to solder like a mad man
last night.
The whole point behind my now discarded ribbon cable scheme was to
1) avoid a tangle of hookup wire and 2) enable easy disconnection.
Twisted wire is a great compromise that achieves both goals /and/ cuts
the hookup length down to a mere 3".
A triple twist is used for stereo signals. It looks like this:
http://mid-8704.kxcdn.com/wp-content/uploads/2016/03/D-B-R-Y-TW-WIRE-22AWG-TWISTED-TRIPLE-BLACK-RED-YELLOW-L.jpg
Plain vanilla twisted pair is used for the power connection. The PCB end
of the hookup bundles are inserted into SIP sockets, which provide the
easy disconnect:
https://www.taydaelectronics.com/media/catalog/product/cache/1/image/500x500/9df78eab33525d08d6e5fb8d27136e95/S/I/SIP_Socket_2_1.jpg

Allow me a small rant about the Cat 5 twisted pair solution that was
discarded along the way to my ultimate hand twisted 26 AWG wire
solution. Although the printed label on the outside of every piece of
Cat 5 twisted pair cable examined by me clearly states "24 AWG," in
actuality, it's 28 AWG every single time.

Thank you, 73,