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Reviews Categories | Specialized Amateur Communication Products | X-Lock VFO Stabilizer Help

Reviews Summary for X-Lock VFO Stabilizer
X-Lock VFO Stabilizer Reviews: 9 Average rating: 5.0/5 MSRP: $(£22.46 ) Inclusive of VAT
Description: The X-Lock locks a VFO to a crystal source to provide drift free operation. This designs takes a fresh approach to the "Huff-Puff" Frequency Locked Loop technique by using a processor to measure frequency and compute correction signals. The X-Lock employs a 100mSec count period to produce 10Hz "lock points" against which the host VFO will be held. Dual regulators are used to supply the digital and analogue sections of the circuit which in turn are optically coupled to produce an exceptionally clean control voltage.

The X-Lock will accept input signals from a few kHz up to 50MHz to provide up over 6 volts of control range. Features include auto lock/unlock during tuning, RIT detection and fast re-lock, power on reset auto centring, and a dual coloured LED to indicate lock and input states.

An adjustable delay of 1 to 15 seconds is applied to halt the correction process once a tuning change has been detected. This feature greatly enhances slow, fine tuning adjustments on the host VFO.

This new version features an improved RF input stage and connectors to remote the Status LED.
Product is in production.
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W5JV Rating: 5/5 May 26, 2017 15:01 Send this review to a friend
Wionderful, Stable, Now the Heart & Pulse of my K1  Time owned: 6 to 12 months
I recently had my K1 serviced by one of the wizards of Elecraft, Don Wilhelm, W3FPR. Don recalibrated my bands, replaced some out of range components, peaked all necessary trimmers (i.e. doing whatever wizards do when they work :-), installed the K-1 backlight, the K6XX CW indicator w/false blink, and finally the X-Lock VFO stabilizer in the process. What I got back was nothing short of a miracle. I heartily recommend this product (the X-Lock) to anyone with a transceiver with a VFO that is free running. Cheers to all.
AA4XX Rating: 5/5 Aug 16, 2015 14:18 Send this review to a friend
Stabilized my K1's VFO  Time owned: 0 to 3 months
My K1's VFO was drifting 100hz/hr and never would settle down after several hours. I built and installed the X-Lock this past week, and followed the helpful installation tips for the K1 found on the X-Lock website. Now my K1 stays frequency locked to my very stable reference rig (Argonaut VI). I was able to install the X-Lock board on the left front side of the K1, using an existing circuit board screw location by substituting a longer screw and a hollow aluminum spacer. It looks like it belongs there, making a very neat installation.
I am extremely pleased with the X-Lock!
GW4OKT Rating: 5/5 Apr 8, 2015 15:09 Send this review to a friend
Excellent  Time owned: 0 to 3 months
I had a tremendous drift (downwards) on my Elecraft K1, 700Hz in the first hour after switch on, followed by a further 300 Hz in the next hour. The X-lock didn't take long to build and install and I was amazed at the result, stable in seconds! Mine is wrapped in bubble wrap and is working fine. I noticed that the frequency range on 40m shifted upwards and the VFO would not go lower than 7.005 MHz, but I think this was due to the proximity of the board (near L1), I simply widened the coil windings on L1 slightly and it was fixed - perfect.
This kit is a must for the K1.
GM0HKS Rating: 5/5 Oct 7, 2013 16:44 Send this review to a friend
X Lock VFO Stabiliser / K1  Time owned: 0 to 3 months
I recently bought and built the Version 3 X lock kit from Cumbria Designs. Very good kit; simple build and test and, having installed it in my Elecraft K1, its as solid as a rock. Great bit of kit and the K1 is all the better for it. Installation in the K1 was kind of tricky but very achievable if you take your time and exercise care when soldering. I had experienced a degree of drift after transmitting with the K1 but now that's all in the past. I will buy another kit for my home brew 40 metre band CW transceiver. The only thing about that is I will have to change its name from " little drifter" hi !
W4OP Rating: 5/5 Nov 20, 2012 17:11 Send this review to a friend
Brilliant!  Time owned: 6 to 12 months
I have had an X-Lock in my Hallicrafters FPM-300 MK II for about a year now. These radios are about unuseable w/o the X-Lock. Because they are PIC based, they can do things that the analog huff&puffs simply cannot: Adjustable dwell time, recognizing RIT etc. A wonderful product with great support.

Dale W4OP
G4AON Rating: 5/5 Nov 20, 2012 10:05 Send this review to a friend
Works great in a K1  Time owned: 0 to 3 months
My Elecraft K1 has always suffered from slow drift, until now! I have always been a little wary of the VFO stabilizers and wondered if they would cope with the use of RIT, etc.

The latest version of X-Lock (version 3) "just works" in a K1, no connections other than supply, VFO RF in and VFO control out.

I am using the supplied parts to control the K1 VFO (100K resistor, 1N4004 diode and 22 pF cap), it locks the VFO from switch on with no drift after that.

73 Dave
WD8SBB Rating: 5/5 Nov 27, 2011 05:03 Send this review to a friend
Excellent. Beats similar products hands down.  Time owned: 6 to 12 months
This product is amazing. Other huff and puff circuits are good, but x-lock is far superior because it understands RIT.

I bought the x-lock for my Drake TR7. I had been looking at huff and puff stabilizers for some time when I found x-lock. I wanted to look into digital modes, and drift can be a killer. Although the TR7 is quite stable after about 15 minutes of warm up time, sometimes 15-20 minutes is my entire window for operation.

I was offered some advise before I build and installed x-lock from Joe KC9LAD. After having x-lock built and installed, I was so impressed that I decided to write up my experiences for other Drake TR7 enthusiasts I know. I also sent my writeup to Cumbria designs and they posted it on their web site.

I have no interests in Cumbria designs or their products. I am just a very satisfied customer.
W6ZBA Rating: 5/5 Aug 23, 2011 14:48 Send this review to a friend
Plug & Play  Time owned: 0 to 3 months
This is a great quality kit; it includes well-written and detailed instructions. Assembly was a breeze (there aren't a lot of parts) and it worked right away. I bought the X-Lock to stabilize my drifty Elecraft K1's VFO. Mission accomplished!
PA0FRI Rating: 5/5 Aug 5, 2009 09:30 Send this review to a friend
Great for the home brewer  Time owned: 0 to 3 months
Although I successfully have used two vintage versions of PA0KSB's Huff and Puff stabilizer, I bought a X-Lock Stabiliser to test the design. I did the test with a Atlas-215x and the "upgraded" Huff and Puff worked very well with its PIC processor system. The VFO of the Atlas was rock stable during a 12 hour experiment.

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