[Elecraft] BIZARRE OFFERING FROM MFJ

[Alan Bloom]

I've long had mixed feelings about MFJ.  They have some very
interesting, innovative, and cost-competitive products.  However
sometimes the quality isn't there.  For example I have an MFJ antenna
analyzer that was intermittent until I fixed a poor ground connection. 
I forget the details, but as I recall the problem was partly one of
design. 

Alan N1AL 

On 2019-04-07 09:28, Wayne Burdick wrote:

> I've used many MFJ products and in have had very little trouble with any of them. For example, I make frequent use an MFJ-223 hand-held VNA -- it's versatile and does the job. I've also used their manual tuners, antenna switches, and portable/mobile whips. They have a very comprehensive product line that's really unique in the industry.
> 
> That said, I do have some suggestions for MFJ's engineering team on how they might improve their ATU. 
> 
> Looking at the photo, I see that they used much smaller toroidal cores for 5 of the 8 inductors in the L network. This could result in excessive heating, especially on the higher bands, at full power into a worst-case match. We specified T68 sized cores to remain conservative based on extensive testing. Also, if you click on the photo to see the details, you'll see what appears to be very inconsistent hand soldering of the SMD components. While this doesn't necessarily worsen performance or reliability, it should be done in a way that inspires confidence in the buyer. (Easy for me to say, of course. We have the luxury of mass-producing these assemblies using automated pick-and-place equipment at our fabricator in Monterey.)
> 
> Wayne
> N6KR