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[K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

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K2QI

[K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

Hello group,

Just wanted to get some advise before I continue with my experiment.

I recently received a new BHI ANEM AF DSP module. It is a mono-only device
and as such, is supplied with a mono 3.5mm patch cable.

Plugging that cable into the K3 only gives me audio to the left channel.
The right channel or ring, I assume is left floating.

This morning, I stopped by Radio Shack and purchased a stereo to mono
adapter that essentially shorts tip and ring thus channeling both L&R
sources into one. With this adapter, I can hear both main and sub receivers
in my left ear.

I however would like to be able to hear the main RX in both ears, so I
purchased another adapter: mono plug to stereo jack.

Basically, the connections will be like this:

[K3]-->[stereo to mono adapter]--->[mono patch cable]--->[ANEM
DSP]---->[mono to stereo adapter]---->[Headphones]

With that said, is it safe to bridge the L&R channels coming out of the K3's
phone jacks, front or rear panel without fear of damaging the amplifier?
The ANEM presents a 22 ohm load to the K3.

Mni tnx,
James K2QI

On Fri, Dec 3, 2010 at 7:04 AM, Monty Shultes <[hidden email]> wrote:

> James, such an adapter would short the stereo outputs together unless it
> were an active mixer. I doubt that it exists.
> Monty K2DLJ
>
>
> > Does anyone know the part number of a Radio Shack or equivalent 3.5mm
> stereo
> > male to 3.5mm mono female adapter that will bridge both L & R channels
> into
> > a single mono source?
> >
> > --
> > 73 de James K2QI
> > President UNARC/4U1UN
> > ______________________________________________________________
>
>

--
73 de James K2QI
President UNARC/4U1UN
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--... ...-- -.. . .--- .- -- . ...

Joe Subich, W4TV-4

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

>> With that said, is it safe to bridge the L&R channels coming out of
>> the K3'sphone jacks, front or rear panel without fear of damaging
>> the amplifier? The ANEM presents a 22 ohm load to the K3.

Yes, it is safe to sum the *headphone* jacks since both the front and
rear panel headphone jacks include 8.4 Ohm resistors in series with
each (tip and ring) output.

*WARNING* do not sum the Speaker output or use a mono cable in the
speaker jack as the speaker output does not include any resistor and
shorting an output (or driving power into an unused output) can
destroy the speaker amplifier.

73,

... Joe, W4TV

On 12/3/2010 11:29 AM, James Sarte (K2QI) wrote:

> Hello group,
>
> Just wanted to get some advise before I continue with my experiment.
>
> I recently received a new BHI ANEM AF DSP module. It is a mono-only device
> and as such, is supplied with a mono 3.5mm patch cable.
>
> Plugging that cable into the K3 only gives me audio to the left channel.
> The right channel or ring, I assume is left floating.
>
> This morning, I stopped by Radio Shack and purchased a stereo to mono
> adapter that essentially shorts tip and ring thus channeling both L&R
> sources into one. With this adapter, I can hear both main and sub receivers
> in my left ear.
>
> I however would like to be able to hear the main RX in both ears, so I
> purchased another adapter: mono plug to stereo jack.
>
> Basically, the connections will be like this:
>
> [K3]-->[stereo to mono adapter]--->[mono patch cable]--->[ANEM
> DSP]---->[mono to stereo adapter]---->[Headphones]
>
> With that said, is it safe to bridge the L&R channels coming out of the K3's
> phone jacks, front or rear panel without fear of damaging the amplifier?
> The ANEM presents a 22 ohm load to the K3.
>
> Mni tnx,
> James K2QI
>
>
> On Fri, Dec 3, 2010 at 7:04 AM, Monty Shultes<[hidden email]> wrote:
>
>> James, such an adapter would short the stereo outputs together unless it
>> were an active mixer. I doubt that it exists.
>> Monty K2DLJ
>>
>>
>>> Does anyone know the part number of a Radio Shack or equivalent 3.5mm
>> stereo
>>> male to 3.5mm mono female adapter that will bridge both L& R channels
>> into
>>> a single mono source?
>>>
>>> --
>>> 73 de James K2QI
>>> President UNARC/4U1UN
>>> ______________________________________________________________
>>
>>
>
>

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K2QI

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

Thank you Joe. That really puts my mind at ease.

Vy 73,
James K2QI

On Fri, Dec 3, 2010 at 12:49 PM, Joe Subich, W4TV <[hidden email]> wrote:

>
> With that said, is it safe to bridge the L&R channels coming out of
>>> the K3'sphone jacks, front or rear panel without fear of damaging
>>>
>>> the amplifier? The ANEM presents a 22 ohm load to the K3.
>>>
>>
> Yes, it is safe to sum the *headphone* jacks since both the front and
> rear panel headphone jacks include 8.4 Ohm resistors in series with
> each (tip and ring) output.
>
> *WARNING* do not sum the Speaker output or use a mono cable in the
> speaker jack as the speaker output does not include any resistor and
> shorting an output (or driving power into an unused output) can
> destroy the speaker amplifier.
>
> 73,
>
> ... Joe, W4TV
>
>

--... ...-- -.. . .--- .- -- . ...

Jim Brown-10

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

In reply to this post by K2QI

On 12/3/2010 8:29 AM, James Sarte (K2QI) wrote:
> Just wanted to get some advise before I continue with my experiment.

Two-circuit 1/8-in plugs should NOT be used at the output of the K3. A
3-circuit plug is needed. Nearly all pre-made patch cables are junk, and
many are wired wrong for our uses. We are hams. We can MAKE our own
patch cables, and we can study the schematics to see how to wire them.
Elecraft schematics are on line. Good quality 1/8-inch connectors are
made by Neutrik and Switchcraft, and are available on line from good pro
audio vendors like Full Compass Systems in WI. I use miniature coax to
build them (like RG174, etc.)

For part numbers, see http://audiosystemsgroup.com/HamInterfacing.pdf
There's a table on one of the slides.

73, Jim Brown K9YC
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K2QI

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

I'm assuming however that a 2 circuit plug into a 3 circuit adapter should
be fine; i.e. plugging a 3.5mm mono plug into 1/4" stereo to 3.5mm stereo
adapter, which is then inserted into the 1/4" phone socket?

Tnx,
James K2QI

On Fri, Dec 3, 2010 at 2:14 PM, Jim Brown <[hidden email]> wrote:

> On 12/3/2010 8:29 AM, James Sarte (K2QI) wrote:
> > Just wanted to get some advise before I continue with my experiment.
>
> Two-circuit 1/8-in plugs should NOT be used at the output of the K3. A
> 3-circuit plug is needed. Nearly all pre-made patch cables are junk, and
> many are wired wrong for our uses. We are hams. We can MAKE our own
> patch cables, and we can study the schematics to see how to wire them.
> Elecraft schematics are on line. Good quality 1/8-inch connectors are
> made by Neutrik and Switchcraft, and are available on line from good pro
> audio vendors like Full Compass Systems in WI. I use miniature coax to
> build them (like RG174, etc.)
>
> For part numbers, see http://audiosystemsgroup.com/HamInterfacing.pdf
> There's a table on one of the slides.
>
> 73, Jim Brown K9YC
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>

--... ...-- -.. . .--- .- -- . ...

alsopb

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

RG-174 is fine for one circuit. I'd really like to find some affordable
shielded dual center conductor stuff somewhere. Yeah, one can always
make two wire twisted pairs, but a good shield and outer jacket ends up
missing. Cat-x is overkill with too many conductors.

73 de Brian/K3KO

On 12/3/2010 19:45, James Sarte (K2QI) wrote:

> I'm assuming however that a 2 circuit plug into a 3 circuit adapter should
> be fine; i.e. plugging a 3.5mm mono plug into 1/4" stereo to 3.5mm stereo
> adapter, which is then inserted into the 1/4" phone socket?
>
> Tnx,
> James K2QI
>
> On Fri, Dec 3, 2010 at 2:14 PM, Jim Brown<[hidden email]> wrote:
>
>> On 12/3/2010 8:29 AM, James Sarte (K2QI) wrote:
>>> Just wanted to get some advise before I continue with my experiment.
>>
>> Two-circuit 1/8-in plugs should NOT be used at the output of the K3. A
>> 3-circuit plug is needed. Nearly all pre-made patch cables are junk, and
>> many are wired wrong for our uses. We are hams. We can MAKE our own
>> patch cables, and we can study the schematics to see how to wire them.
>> Elecraft schematics are on line. Good quality 1/8-inch connectors are
>> made by Neutrik and Switchcraft, and are available on line from good pro
>> audio vendors like Full Compass Systems in WI. I use miniature coax to
>> build them (like RG174, etc.)
>>
>> For part numbers, see http://audiosystemsgroup.com/HamInterfacing.pdf
>> There's a table on one of the slides.
>>
>> 73, Jim Brown K9YC
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>>
>
>
>

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Joe Subich, W4TV-4

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

In reply to this post by K2QI

> I'm assuming however that a 2 circuit plug into a 3 circuit adapter
> should be fine; i.e. plugging a 3.5mm mono plug into 1/4" stereo to
> 3.5mm stereo adapter, which is then inserted into the 1/4" phone
> socket?

No! Connecting a 2 circuit plug to a three circuit jack with tip
and ring used will short the ring to the sleeve (typically ground).

Plugging a 2 circuit cable into a mono (2 circuit plug) to stereo
(3 circuit jack) adapter will short all output since the mono to
stereo adapter simply connects the tip to tip and ring.

73,

... Joe, W4TV

On 12/3/2010 2:45 PM, James Sarte (K2QI) wrote:

Don Wilhelm-4

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

In reply to this post by K2QI

James,

That is incorrect. If you plug a 3.5mm mono plug into the adapter, it
will short between the ring and sleeve on the 1/4 inch side too.

73,
Don W3FPR

On 12/3/2010 2:45 PM, James Sarte (K2QI) wrote:
> I'm assuming however that a 2 circuit plug into a 3 circuit adapter should
> be fine; i.e. plugging a 3.5mm mono plug into 1/4" stereo to 3.5mm stereo
> adapter, which is then inserted into the 1/4" phone socket?
>
> Tnx,
> James K2QI
>
______________________________________________________________
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K2QI

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

Thanks Don.

I have decided to forego the the 1/4" to 1/8" adapter for the front phone
jack. I am now plugging the 1/8" mono cable and plug directly into the rear
phone jack. To get audio to both cans, I am using a mono to stereo adapter
between the offboard DSP and my headphones. Seems to work fine, and can now
get sub rx audio to both cans as well after adjusting the L-MIX-R settings
to Ab - b.

In the end, I guess I overcomplicated matters. I just wanted to ensure that
inserting a mono plug into either front or rear phone jacks would be fine.

Tnx,
James

On Fri, Dec 3, 2010 at 3:38 PM, Don Wilhelm <[hidden email]> wrote:

> James,
>
> That is incorrect. If you plug a 3.5mm mono plug into the adapter, it will
> short between the ring and sleeve on the 1/4 inch side too.
>
> 73,
> Don W3FPR
>
>
>

--... ...-- -.. . .--- .- -- . ...

Jim Brown-10

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

In reply to this post by alsopb

On 12/3/2010 12:16 PM, Brian Alsop wrote:
> I'd really like to find some affordable
> shielded dual center conductor stuff somewhere.

Belden makes (or at least used to make) 1901A, which is a miniature
twisted pair with a braid shield. I have some, and make some patch
cables with it. It's quite nice. Another very good cable company,
Gepco, makes an equivalent that they call X-band or something like that.

73, Jim K9YC
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k6dgw

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

In reply to this post by Don Wilhelm-4

What is a "3-circuit phone plug?" I know about 1-circuit plugs
[tip-sleeve providing one circuit] and 2-circuit plugs [tip-ring-sleeve
providing two circuits -- tip-sleeve and ring-sleeve]. Is this
referring to 2-wire and 3-wire plugs? I've seen on the list here that
the wrong plug will blow the AF amplifier.

I followed the legends on the back panel and I don't use the front panel
mic or headfone jacks. Where it said MONO, I use a 1-circuit plug,
STEREO gets a 2-circuit plug. I use cables from Radio Shack between
sound card and radio and they seem to work fine. I really hope I'm not
screwing something up in my radio.

73,

Fred K6DGW
- Northern California Contest Club
- CU in the 2011 Cal QSO Party 1-2 Oct 2011
- www.cqp.org

On 12/3/2010 12:38 PM, Don Wilhelm wrote:

> James,
>
> That is incorrect. If you plug a 3.5mm mono plug into the adapter, it
> will short between the ring and sleeve on the 1/4 inch side too.
>
> 73,
> Don W3FPR
>
> On 12/3/2010 2:45 PM, James Sarte (K2QI) wrote:
>> I'm assuming however that a 2 circuit plug into a 3 circuit adapter should
>> be fine; i.e. plugging a 3.5mm mono plug into 1/4" stereo to 3.5mm stereo
>> adapter, which is then inserted into the 1/4" phone socket?
>>
>> Tnx,
>> James K2QI

Don Wilhelm-4

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

Fred,

That "circuit" nomenclature has a lot of other people confused, and even
some confusion has crept into parts catalogs (but not the mainstream
distributors). I have seen stereo plugs and jacks called both 2 circuit
and 3 circuit - I guess they might refer to the number of pins - then
there may be extra contacts in the jack and I have seen a mono jack with
a closed circuit output pin also referred to as a 3 circuit jack - I
guess was because it has 3 pins (circuits?). Talk about being confused
- and frustrated after you receive the order - I won't order from that
source again.

73,
Don W3FPR

On 12/3/2010 5:03 PM, Fred Jensen wrote:

> What is a "3-circuit phone plug?" I know about 1-circuit plugs
> [tip-sleeve providing one circuit] and 2-circuit plugs [tip-ring-sleeve
> providing two circuits -- tip-sleeve and ring-sleeve]. Is this
> referring to 2-wire and 3-wire plugs? I've seen on the list here that
> the wrong plug will blow the AF amplifier.
>
> I followed the legends on the back panel and I don't use the front panel
> mic or headfone jacks. Where it said MONO, I use a 1-circuit plug,
> STEREO gets a 2-circuit plug. I use cables from Radio Shack between
> sound card and radio and they seem to work fine. I really hope I'm not
> screwing something up in my radio.
>
> 73,
>
> Fred K6DGW
> - Northern California Contest Club
> - CU in the 2011 Cal QSO Party 1-2 Oct 2011
> - www.cqp.org
>
> On 12/3/2010 12:38 PM, Don Wilhelm wrote:
>> James,
>>
>> That is incorrect. If you plug a 3.5mm mono plug into the adapter, it
>> will short between the ring and sleeve on the 1/4 inch side too.
>>
>> 73,
>> Don W3FPR
>>
>> On 12/3/2010 2:45 PM, James Sarte (K2QI) wrote:
>>> I'm assuming however that a 2 circuit plug into a 3 circuit adapter should
>>> be fine; i.e. plugging a 3.5mm mono plug into 1/4" stereo to 3.5mm stereo
>>> adapter, which is then inserted into the 1/4" phone socket?
>>>
>>> Tnx,
>>> James K2QI
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html
>

K2QI

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

OK, now I'm REALLY confused.

From what I've read on the reflector, and what others have told me, it
is OK to insert a mono plug into either the front or rear phone jacks.
It was also made very clear that inserting a mono plug into the rear
SPKR jack was a big no-no, even if the settings were set to SPKRS=1.

Now, I just got an email from Dale Farmer who told me that I should
not insert a mono plug into the phone jacks, as the plug will
obviously short the amplifier channels. On the other hand, and
contrary to what everyone else told me, he said it was OK to insert a
mono plug into the SPKR jack as long as speakers setting was 1. His
reasoning was, that if speakers were set 1 in the menu, the right
channel amp would be isolated and thus no damage could happen.

But here's what confuses me. According to page 20 of the manual, it states:

> PHONES
>
> STEREO or MONO; 16
>
> The front and rear-panel headphone jacks are both
>isolated with series resistors. This allows you to use
>mono phones on one jack and stereo on the other, if
>required. You’ll need stereo phones for AFX (audio
>effects) and stereo dual receive (with sub receiver).
>Ω min. recommended

Now what am I to believe here??? If I understand what was written in
the manual, then it's ok to use a mono plug in those jacks as they're
buffered by a series of resistors.

73,
James K2QI
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--... ...-- -.. . .--- .- -- . ...

Jim Brown-10

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

In reply to this post by k6dgw

On 12/3/2010 2:03 PM, Fred Jensen wrote:
> What is a "3-circuit phone plug?"

One with three contacts -- Tip, Ring, and Sleeve. Often used for stereo
headphones, and thus called a stereo plug.

73, Jim K9YC
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Jim Brown-10

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

In reply to this post by K2QI

On 12/3/2010 2:31 PM, James Sarte (K2QI) wrote:
> Now what am I to believe here??? If I understand what was written in
> the manual, then it's ok to use a mono plug in those jacks as they're
> buffered by a series of resistors.
>

The manual is correct -- the HEADPHONE output is isolated with
resistors. The SPEAKER output is NOT, and putting a two-circuit plug
(mono plug) into it can cause the output chip to fail destructively.

Again, the SCHEMATICS are on line. Study them. We're hams. We passed
exams showing that we know this stuff.

73, Jim K9YC
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K2QI

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

I will have a look a the schematics tonight after dinner; just find it
a bit hard to believe that I'd get conflicting information direct from
Aptos.

Tnx,
James K2QI

On Fri, Dec 3, 2010 at 5:57 PM, Jim Brown <[hidden email]> wrote:

>
> The manual is correct -- the HEADPHONE output is isolated with
> resistors. The SPEAKER output is NOT, and putting a two-circuit plug
> (mono plug) into it can cause the output chip to fail destructively.
>
> Again, the SCHEMATICS are on line. Study them. We're hams. We passed
> exams showing that we know this stuff.
>
> 73, Jim K9YC
> ______________________________________________________________

--... ...-- -.. . .--- .- -- . ...

P.B. Christensen

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

Jim (K9YC) is right. When looking at the K3 schematic, realize that the
headphone amp's 8-ohm build-out resistors are not on the same schematic page
as the headphone amp. At least it wasn't the last time I looked.

Paul, W9AC

----- Original Message -----
From: "James Sarte (K2QI)" <[hidden email]>
To: <[hidden email]>
Cc: <[hidden email]>
Sent: Friday, December 03, 2010 6:08 PM
Subject: Re: [Elecraft] [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo
to mono adapters)

I will have a look a the schematics tonight after dinner; just find it
a bit hard to believe that I'd get conflicting information direct from
Aptos.

Tnx,
James K2QI

On Fri, Dec 3, 2010 at 5:57 PM, Jim Brown <[hidden email]> wrote:
>
> The manual is correct -- the HEADPHONE output is isolated with
> resistors. The SPEAKER output is NOT, and putting a two-circuit plug
> (mono plug) into it can cause the output chip to fail destructively.
>
> Again, the SCHEMATICS are on line. Study them. We're hams. We passed
> exams showing that we know this stuff.
>
> 73, Jim K9YC

______________________________________________________________
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Steve Ellington

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

In reply to this post by Jim Brown-10

How could a 2 circuit plug be mono since there is only 1 circuit?
N4LQ
Steve

----- Original Message -----
From: "Jim Brown" <[hidden email]>
To: <[hidden email]>
Sent: Friday, December 03, 2010 5:57 PM
Subject: Re: [Elecraft] [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo
to mono adapters)

> On 12/3/2010 2:31 PM, James Sarte (K2QI) wrote:
>> Now what am I to believe here??? If I understand what was written in
>> the manual, then it's ok to use a mono plug in those jacks as they're
>> buffered by a series of resistors.
>>
>
> The manual is correct -- the HEADPHONE output is isolated with
> resistors. The SPEAKER output is NOT, and putting a two-circuit plug
> (mono plug) into it can cause the output chip to fail destructively.
>
> Again, the SCHEMATICS are on line. Study them. We're hams. We passed
> exams showing that we know this stuff.
>
> 73, Jim K9YC
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list: http://www.qsl.net/donate.html

K2QI

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

In reply to this post by P.B. Christensen

BTW, one thing I noticed is that both stereo to mono adapters I
purchased short ring and tip together rather than ring to sleeve.
Since both hot signals are combined, isn't there still a load being
presented to the right channel amp?

I know some adapters will short ring to sleeve, thereby presenting a 0
ohm load to the amp. In this case, that isn't happening.

My ohm meter shows when using a stereo to mono adapter while connected
to the mono DSP, ring and sleeve show a 22 ohm load; tip and sleeve
show a 22 ohm load, and ring and tip have a 1 ohm load as they're
shorted.

Seems safe to me?

Tnx,
James K2QI

On Fri, Dec 3, 2010 at 6:14 PM, Paul Christensen <[hidden email]> wrote:
> Jim (K9YC) is right. When looking at the K3 schematic, realize that the
> headphone amp's 8-ohm build-out resistors are not on the same schematic page
> as the headphone amp. At least it wasn't the last time I looked.
>
> Paul, W9AC
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K2QI

Re: [K3] Shorting K3 PHONE jack outputs (WAS OT: Stereo to mono adapters)

One last experiment showed that with a standard stereo 1/4" to 1/8"
reducer with a mono 1/8" device connected to the end, ring and sleeve
showed a 0 ohm load.

So it seems to me that the RS adapters that short ring and tip rather
than ring and sleeve should be OK for use with the K3.

Tnx,
James K2QI

On Fri, Dec 3, 2010 at 11:53 PM, James Sarte (K2QI) <[hidden email]> wrote:

> BTW, one thing I noticed is that both stereo to mono adapters I
> purchased short ring and tip together rather than ring to sleeve.
> Since both hot signals are combined, isn't there still a load being
> presented to the right channel amp?
>
> I know some adapters will short ring to sleeve, thereby presenting a 0
> ohm load to the amp. In this case, that isn't happening.
>
> My ohm meter shows when using a stereo to mono adapter while connected
> to the mono DSP, ring and sleeve show a 22 ohm load; tip and sleeve
> show a 22 ohm load, and ring and tip have a 1 ohm load as they're
> shorted.
>
> Seems safe to me?
>
> Tnx,
> James K2QI
>
>
>

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