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[K2] Setting audio drive level when using VOX

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gareth.m5kvk

[K2] Setting audio drive level when using VOX

Hi
I think I may have a problem somewhere in my audio chain. I say may because
what I'm seeing may be correct: I'm not sure.

I have a Windows 7 PC running DM780 with a Tascam US2X2 connected via a
20dB pad (10k/1k) to the Mic connector on the K2. I am using VOX, so
there's no other connection.

When I increase the Line Out on the Tascam to point at which the VOX
operates, I immediately see one bar on the ALC. The bar is pretty steady:
maybe very slight flashing. Regardless of further Line Out increases, I
never see more than one bar.

I understood that the drive level should be adjusted to the point of one
bar ALC and then backed off slightly so that ALC is only flashing
occasionally. If I back off even slightly, the VOX drops out.

Is this an artifact of the VOX? i.e. the VOX activation level is too high?
Is it an indication that the 20dB pad is too high? Or is this normal and I
just adjust Line Out until the VOX opens and then leave it there: even
though one bar of ALC is on.

73, Gareth - M5KVK
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Don Wilhelm-4

Re: [K2] Setting audio drive level when using VOX

Gareth,

The VOX on the K2 is the weak point in the KSB2 design. You will be
better off using PTT on the K2.
A simple "one transistor keying" circuit can be added to the serial port
RTS or DTR (which depends on your software) to trigger the K2 PTT will
give you reliable operation.

73,
Don W3FPR

On 8/18/2015 4:49 AM, Gareth - M5KVK wrote:

> Hi
> I think I may have a problem somewhere in my audio chain. I say may because
> what I'm seeing may be correct: I'm not sure.
>
> I have a Windows 7 PC running DM780 with a Tascam US2X2 connected via a
> 20dB pad (10k/1k) to the Mic connector on the K2. I am using VOX, so
> there's no other connection.
>
> When I increase the Line Out on the Tascam to point at which the VOX
> operates, I immediately see one bar on the ALC. The bar is pretty steady:
> maybe very slight flashing. Regardless of further Line Out increases, I
> never see more than one bar.
>
> I understood that the drive level should be adjusted to the point of one
> bar ALC and then backed off slightly so that ALC is only flashing
> occasionally. If I back off even slightly, the VOX drops out.
>
> Is this an artifact of the VOX? i.e. the VOX activation level is too high?
> Is it an indication that the 20dB pad is too high? Or is this normal and I
> just adjust Line Out until the VOX opens and then leave it there: even
> though one bar of ALC is on.
>
>

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m5kvk

Re: [K2] Setting audio drive level when using VOX

Aah, that would explain it.
Nomatter, I’ll connect up the CAT and use that.

Thanks, Don
73

Gareth - M5KVK
[hidden email]
[hidden email]

> On 18 Aug 2015, at 12:30, Don Wilhelm <[hidden email]> wrote:
>
> Gareth,
>
> The VOX on the K2 is the weak point in the KSB2 design. You will be better off using PTT on the K2.
> A simple "one transistor keying" circuit can be added to the serial port RTS or DTR (which depends on your software) to trigger the K2 PTT will give you reliable operation.
>
> 73,
> Don W3FPR
>
> On 8/18/2015 4:49 AM, Gareth - M5KVK wrote:
>> Hi
>> I think I may have a problem somewhere in my audio chain. I say may because
>> what I'm seeing may be correct: I'm not sure.
>>
>> I have a Windows 7 PC running DM780 with a Tascam US2X2 connected via a
>> 20dB pad (10k/1k) to the Mic connector on the K2. I am using VOX, so
>> there's no other connection.
>>
>> When I increase the Line Out on the Tascam to point at which the VOX
>> operates, I immediately see one bar on the ALC. The bar is pretty steady:
>> maybe very slight flashing. Regardless of further Line Out increases, I
>> never see more than one bar.
>>
>> I understood that the drive level should be adjusted to the point of one
>> bar ALC and then backed off slightly so that ALC is only flashing
>> occasionally. If I back off even slightly, the VOX drops out.
>>
>> Is this an artifact of the VOX? i.e. the VOX activation level is too high?
>> Is it an indication that the 20dB pad is too high? Or is this normal and I
>> just adjust Line Out until the VOX opens and then leave it there: even
>> though one bar of ALC is on.
>>
>>
>