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Re: K1 IF Amp Mod? Some history.

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Mike Morrow-3

Re: K1 IF Amp Mod? Some history.

> ...were not available when the K1 was designed 20 years or so ago.

That's a pretty fanciful date to just pick out of thin air! :-)

There wasn't anything that was "Elecraft" 20 years ago. The K1 was shown
first at Dayton 2000, after which many of us ordered one. The first
deliveries to the mass unwashed customer base were made in October, 2000,
after a wait of more than five months.

I got No. 175 in November, 2000. Not 1994!

It's already been noted that the Sierra (also designed by Wayne/N6KR) came
out long before the K1...in fact...in 1994. So there's your 20 years!

Mike / KK5F
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Eric Swartz - WA6HHQ

Re: K1 IF Amp Mod? Some history.

Administrator

More history - Elecraft was formally created July of 1998. (We began working on
the K2 design well before that.)

We shipped the first 100 K2 Field Test Units January and Feb. of 1999. We took
orders for production K2 kits at Dayton in May of 1999.

We followed that with the K1, then the KX1, the K3, and most recently the KX3.

73,

Eric
elecraft.com

On 10/17/2014 5:40 PM, Mike Morrow wrote:

>> ...were not available when the K1 was designed 20 years or so ago.
>>
>> That's a pretty fanciful date to just pick out of thin air! :-)
>>
>> There wasn't anything that was "Elecraft" 20 years ago. The K1 was shown
>> first at Dayton 2000, after which many of us ordered one. The first
>> deliveries to the mass unwashed customer base were made in October, 2000,
>> after a wait of more than five months.
>>
>> I got No. 175 in November, 2000. Not 1994!
>>
>> It's already been noted that the Sierra (also designed by Wayne/N6KR) came
>> out long before the K1...in fact...in 1994. So there's your 20 years!
>>
>> Mike / KK5F

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r j

Re: K1 IF Amp Mod? Some history.

Well ... Thanks for the history. One can also look at Elecraft's website

http://www.elecraft.com/about_elecraft.htm

But my question remains: Why did the (very early) Sierra and the (first
Elecraft product) K2 have IF amp (MC1350 - and of course the standard AF
amp LM386), but the K1 was equipped with no IF amp but two AF amps (LM386
and LM380) and an accordingly somewhat problematic AF based AGC.

Thanks.
Roy
RF Tinkerer

On Sat, Oct 18, 2014 at 8:34 AM, Eric Swartz - WA6HHQ, Elecraft <
[hidden email]> wrote:

> More history - Elecraft was formally created July of 1998. (We began
> working on the K2 design well before that.)
>
> We shipped the first 100 K2 Field Test Units January and Feb. of 1999. We
> took orders for production K2 kits at Dayton in May of 1999.
>
> We followed that with the K1, then the KX1, the K3, and most recently the
> KX3.
>
> 73,
>
> Eric
> elecraft.com
>
>
> On 10/17/2014 5:40 PM, Mike Morrow wrote:
>
>> ...were not available when the K1 was designed 20 years or so ago.
>>>
>>> That's a pretty fanciful date to just pick out of thin air! :-)
>>>
>>> There wasn't anything that was "Elecraft" 20 years ago. The K1 was shown
>>> first at Dayton 2000, after which many of us ordered one. The first
>>> deliveries to the mass unwashed customer base were made in October, 2000,
>>> after a wait of more than five months.
>>>
>>> I got No. 175 in November, 2000. Not 1994!
>>>
>>> It's already been noted that the Sierra (also designed by Wayne/N6KR)
>>> came
>>> out long before the K1...in fact...in 1994. So there's your 20 years!
>>>
>>> Mike / KK5F
>>>
>> ______________________________________________________________
> 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
> Message delivered to [hidden email]
>

Don Wilhelm-4

Re: K1 IF Amp Mod? Some history.

Roy,

I think one of the reasons for the change from the MC1350 to the NE612
followed by the LM386 was due to the fact that when the K1 was designed,
the MC1350 in its DIP format was "not to be used for current designs".
Yes, the MC1350 is still available in SMD format, and Elecraft has
designed a carrier board that allows its use in the DIP format holes
(for the K2 ongoing support).

To redesign the the K1 to use the MC1350 would be challenging. The AGC
system would have to be changed to use that part. There is nothing
wrong with the "dual NE612" designs - there are several out there, and
they perform quite nicely.

BTW - the K2 used the LM380-8 audio amplifier, not the LM386.

73,
Don W3FPR

On 10/17/2014 9:50 PM, r j wrote:

> Well ... Thanks for the history. One can also look at Elecraft's website
>
> http://www.elecraft.com/about_elecraft.htm
>
>
> But my question remains: Why did the (very early) Sierra and the (first
> Elecraft product) K2 have IF amp (MC1350 - and of course the standard AF
> amp LM386), but the K1 was equipped with no IF amp but two AF amps (LM386
> and LM380) and an accordingly somewhat problematic AF based AGC.
>
> Thanks.
> Roy
> RF Tinkerer
>
> On Sat, Oct 18, 2014 at 8:34 AM, Eric Swartz - WA6HHQ, Elecraft <
> [hidden email]> wrote:
>
>> More history - Elecraft was formally created July of 1998. (We began
>> working on the K2 design well before that.)
>>
>> We shipped the first 100 K2 Field Test Units January and Feb. of 1999. We
>> took orders for production K2 kits at Dayton in May of 1999.
>>
>> We followed that with the K1, then the KX1, the K3, and most recently the
>> KX3.
>>
>> 73,
>>
>> Eric
>> elecraft.com
>>
>>

r j

Re: K1 IF Amp Mod? Some history.

Yep - the K2 uses LM380, but the Sierra uses only an LM386 as headphone
amp. My ill formulated sentence. But it doesn't matter - its all AF dBs.

My point is that the Sierra and the K2 uses an IF amp MC1350 before the
product detector 602 (612, NE, SA ...), and gets a 'proper' AGC. The K2 is
of course a better design since it uses a TUF-1 mixer (w. pre- and post
amp) in stead of the 602 mixer.

But the K1 - a later design then the Sierra and K2 - is imo one step back
and down by not having an IF amp. The main rcvr guts of the K1 looks
something like:

602 MIXER - XFIL - 602 PROD DET - LM386 AF PRE AMP - LM380 AF POWER AMP

There is no IF amplification, and the AGC is based on the very slow CW AF
signal.

Anyway - it is a piece of cake to mod the K1. Quite a few of the other QRP
rigs (in addition to the Sierra) from the period are 602-1350-602. I just
wanted to know why they chose the all AF way. I guess someone has asked
before - but the answer is imo not all clear.

http://elecraft.365791.n2.nabble.com/RE-Re-K1-AGC-time-constant-and-how-to-radically-improveK1-AGC-td388515.html

Roy
RF Tinkerer

On Sat, Oct 18, 2014 at 9:37 AM, Don Wilhelm <[hidden email]> wrote:

> Roy,
>
> I think one of the reasons for the change from the MC1350 to the NE612
> followed by the LM386 was due to the fact that when the K1 was designed,
> the MC1350 in its DIP format was "not to be used for current designs".
> Yes, the MC1350 is still available in SMD format, and Elecraft has designed
> a carrier board that allows its use in the DIP format holes (for the K2
> ongoing support).
>
> To redesign the the K1 to use the MC1350 would be challenging. The AGC
> system would have to be changed to use that part. There is nothing wrong
> with the "dual NE612" designs - there are several out there, and they
> perform quite nicely.
>
> BTW - the K2 used the LM380-8 audio amplifier, not the LM386.
>
> 73,
> Don W3FPR
>
>
> On 10/17/2014 9:50 PM, r j wrote:
>
>> Well ... Thanks for the history. One can also look at Elecraft's website
>>
>> http://www.elecraft.com/about_elecraft.htm
>>
>>
>> But my question remains: Why did the (very early) Sierra and the (first
>> Elecraft product) K2 have IF amp (MC1350 - and of course the standard AF
>> amp LM386), but the K1 was equipped with no IF amp but two AF amps (LM386
>> and LM380) and an accordingly somewhat problematic AF based AGC.
>>
>> Thanks.
>> Roy
>> RF Tinkerer
>>
>> On Sat, Oct 18, 2014 at 8:34 AM, Eric Swartz - WA6HHQ, Elecraft <
>> [hidden email]> wrote:
>>
>> More history - Elecraft was formally created July of 1998. (We began
>>> working on the K2 design well before that.)
>>>
>>> We shipped the first 100 K2 Field Test Units January and Feb. of 1999.
>>> We
>>> took orders for production K2 kits at Dayton in May of 1999.
>>>
>>> We followed that with the K1, then the KX1, the K3, and most recently the
>>> KX3.
>>>
>>> 73,
>>>
>>> Eric
>>> elecraft.com
>>>
>>>
>>>
>

Phil Wheeler-2

Re: K1 IF Amp Mod? Some history.

In reply to this post by Eric Swartz - WA6HHQ

Hmm .. so where is the KX2, Eric? :-)

73, Phil W7OX

On 10/17/14, 6:34 PM, Eric Swartz - WA6HHQ,
Elecraft wrote:

> More history - Elecraft was formally created
> July of 1998. (We began working on the K2 design
> well before that.)
>
> We shipped the first 100 K2 Field Test Units
> January and Feb. of 1999. We took orders for
> production K2 kits at Dayton in May of 1999.
>
> We followed that with the K1, then the KX1, the
> K3, and most recently the KX3.
>
> 73,
>
> Eric
> elecraft.com
>
> On 10/17/2014 5:40 PM, Mike Morrow wrote:
>>> ...were not available when the K1 was designed
>>> 20 years or so ago.
>>>
>>> That's a pretty fanciful date to just pick out
>>> of thin air! :-)
>>>
>>> There wasn't anything that was "Elecraft" 20
>>> years ago. The K1 was shown
>>> first at Dayton 2000, after which many of us
>>> ordered one. The first
>>> deliveries to the mass unwashed customer base
>>> were made in October, 2000,
>>> after a wait of more than five months.
>>>
>>> I got No. 175 in November, 2000. Not 1994!
>>>
>>> It's already been noted that the Sierra (also
>>> designed by Wayne/N6KR) came
>>> out long before the K1...in fact...in 1994.
>>> So there's your 20 years!
>>>
>>> Mike / KK5F