Subject: K1: BoomBox & Mojo to go...
Date:    Fri, 14 Jul 2000 12:15:23 -0700
From:    Radman <radman@best.com>
To:      elecraft@qth.net, qrp-l@Lehigh.EDU


Gang,

The 1984 release of the 'rockumentary' B-Grade film spoof, "Spinal Tap," shook the cult film world when heavy metal lead guitarist, Ian Tufnel spilled the beans. Whilst the volume setting on other rock bands' equipment goes to 10, 'Spinal Tap' goes to 11. Is there really a difference? Ian explains, "Yeah, well it's like... one louder, innit?"

Yesterday, I got my hands on the *finished* K1 transceiver for a brief demo, and clearly Wayne Burdick and Ian Tufnel agree - 11 is louder than 10. The K1 now sports a beefed AF strip and revamped audio-derived AGC that  is impressive in three ways - the AGC is wonderfully effective, the max-audio setting offers more loudness than any mobile op will ever need, and the RX current penalty for all this is a mere 5 mA - with a bit more current draw for AF Gain set to "11."

For those less interested in bolting the K1 to the handlebars of their Harley, Elecraft will offer an app note to "tame" the AF gain control to room-listening levels - just swapping a bypass cap will do it. I found the stock scheme very usable as is, although I would probably run the AF Gain at about 9-10 o'clock - with 6 o'clock equal to Spinal Tap value = 11. As you roll the AF gain up (louder) you can actually drive the K1 speaker so hard that it will start to clip - somewhere between Spinal Tap value 10-11.

Now, here's the cool part - if you're not mobile, you'll have plenty of AF to drive a nice big console speaker with the K1. We attached the accessory speaker for the ICOM 730 - about the size of a shoe box - to the K1 and it sounded great. The larger enclosure allows better bass response. I also tested the new AF strip with studio grade Sony headphones and I found it to be "hiss-free" at normal audio levels. And, if the bands are totally trashed you could simply plug your Walkman into the K1 and listen to the Spinal Tap soundtrack at volume = 11. It would be monaural but very 
loud!

So how does the K1 play? Wayne and I cruised the bands at midday - poor conditions - but we easily bagged a guy in Arizona running 500 watts to a yagi. We were running 5 watts to a wimpy wire. We exchanged 5x9s each way -  good demonstration of K1 mojo under poor conditions. We signed with him and  cranked the RF power up to ~ 8 watts and went brick-on-key into a dummy load. Power output looked very stable. Then we rolled the power back down to 5 watts and went key-down for minutes and checked-out the heat sink - barely warm to the touch. The K1 PA is the same transistor used in the K2 PA scheme - just a single unit instead of a pair. It's beefy, conservative and cool-running.

Next, Wayne wanted to show-off the K1's spiffy break-in keying features. This naturally lead to a copying-between-the-dits contest at 40 to 50 wpm. While I was literally blown away by the AF section, the keying/break-in characteristics of the K1 really claim the bragging rights in this review.  The little K1 is one of the cleanest CW rigs I've ever used. Wayne hints that the K1 might be his lifetime personal-best in keying/break-in design - ultra clean  - no clicks, no chirps, no leading artifacts, no trailing artifacts. Just pure CW music. I wouldn't say it smokes the K2 - but it's the finest keying rig near its  price-point that I've ever used.

What about the internal battery option? Elecraft says, first things first!  They've finished the design and now it's a matter of scrambling to get all  the components in and the documentation finished. Field test is coming, but not immediately.

The really good news is there won't be a raft of after-market K1 mods for AF Gain, RF-Out or keying characteristics - that's already been designed by Elecraft. And, if you want a 'taste' of K1 AF-Gain, just rent a copy of 'Spinal Tap'  - that should keep you entertained!

Stay tuned,
Conrad Weiss - NN6CW