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Reviews For: Nye Viking MB-II Tuner

Category: Antenna Tuners/Matching Networks

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Review Summary For : Nye Viking MB-II Tuner
Reviews: 5MSRP: 700 approx.
Description:
Antenna impedance matching network incorporating a Pi network consisting of a large variable, copper ribbon inductor, a split section high voltage variable capacitor and a bank of high voltage fixed capacitors. Capable of handling power in excess of 2000 watts into loads between 40 and 2000 ohms.
Product is not in production
More Info: http://
# last 180 days Avg. Rating last 180 days Total reviews Avg. overall rating
0055
WA7KGX Rating: 2014-11-10
Finally beginning to Appreciate it. Time Owned: more than 12 months.
There appear to be different versions of the MB-II. As far as I know, all use a PI network. The output capacitor is wide spaced for high voltage but does not have enough range to tune some loads. Fixed capacitors can be switched in as needed.

Some older units used "homebrew" caps made out of aluminium discs and teflon dielectric. These had a tendency to fail under high power high voltage conditions. Later units used high voltage doorknob caps for this purpose.

I bought mine in the 1970s. The teflon caps burned out matching a random length wire on 75 meters when driven by a Dentron MLA-2500. I switched out the caps and added an awe inspiring transmitting variable sitting on the top of the box.

Fast forward to the present. I am now using a Cobra Senior multiband dipole. An MFJ-993B matched it easily but is limited to running barefoot.

I tried my Nye Viking with the Cobra but did not get an exact match on 160. So I started modding it. I ended up with real transmitting caps in place of the teflon jobs except for the input cap.

I changed the output balun to an input transformer and lifted the matching network off the ground. Moving the balun to the input keeps high RF voltage from saturating the ferrite.

I added an external coil so I could tune 160 on the Cobra. With this setup I was able to run 900 watts for a minute or two on 160. Some parts were slightly warm to the touch. All the other tuners I've tried arced or smoked.

After trying a Heathkit sa2060a which almost did the job but tended to arc on 160, I gave the Nye Viking another try. The Nye Viking still would not give an exact match on 160 but it was better than 2:1 on the frequencies I tried. As before, with the Drake L7 claiming 900 watts output the Nye Viking was barely warm to the touch after a minute or two. The trick was not insisting on a 1:1 match! The FlexRadio 5000a and Drake L7 can deal with 2:1 or less, which the Nye Viking was able to provide.

I don't know if an unmodified Nye Viking will tune 160 with the Cobra Senior without the mods I made. It is nice to know that the lion's share of my transmitting power is now going to the antenna instead of the tuner.


AA5AZ Rating: 2013-06-02
It's everything it says it is! Time Owned: 0 to 3 months.
It's an antenna tuner, but a very, very excellent tuner. The only gripe I have is it's lack of a separate power and SWR. The power meter on here is worthless, but the SWR is very accurate.

I couldn't find the manual anywhere on the Internet to download. Here's the link to my dropbox: http://goo.gl/8QYq7
W3NA Rating: 2012-03-31
Best yet Time Owned: more than 12 months.
I purchased this tuner about 5 years ago because of high praise and ratings. It sat on a shelf as backup, to my Heathkit SA-2040 which was doing a fine job with my antennas, rig, and SB-220 at about 1000W output. Then, I purchased a legal limit amplifier and the landscape changed. I noticed that the Heathkit could handle 1500 W power under most circumstances but components would get warm under the right conditions which made me nervous.
So, I decided to check out my Nye Viking MB-II. When I removed the cabinet top, holy cow! it looks like it is built from broadcast transmitter components. Suddenly my faithful Heathkit tuner looked like a toy. I have owned a Johnson KW Matchbox and it was not as heavy duty as my MB-II, even though the KW Matchbox is in a much larger cabinet.
I sold the Heathkit SA-2040 and have never looked back. The MB-II is smooth, reproducible, tunes most anything, and stays cool under all my conditions. And, it has a smaller footprint than the Heathkit.
AB2CF Rating: 2010-05-15
Quality through and through Time Owned: 0 to 3 months.
After nearly two decades with the Drake MN-2000 I bid and won an MB-II on Epay. Got it for a great price and am in awe of it. You'd be hard put to see a better built tuner. Quality through and through.
For now I'm limited to a 40m loop in the attic. The Drake did well but could only tune the top of 75m though 10m. Boy i missed my 80m CW.
Well, got the NYE hooked it up and 40m was a breeze. OK for Ha-Ha's let me try 80m. Tuned the loop with ease and sigs were strong. OK, 160m. Ha, doubt it. Was I wrong. That 40m loop was pulling sigs in and 1:1 SWR. IMPRESSIVE.

Well I had to pop the hood and see what does that magic. And did I.
You can see why the MB-II is rated for 3 KW. The word Overkill is in the design specs.
Now I know why they were so expensive. Quality like this does not come cheap.
Rating it a "5" is almost an insult to it.
I'll be a silent key before it leaves my shack.
N6NKN Rating: 2007-05-26
Tough As Nails Time Owned: 6 to 12 months.
Nye Viking tuners bear a strong resemblance to the Johnson Matchbox. They should. Mr. Nye bought the rights to build a Johnson Matchbox equalivent.

I'm using my MB-II with a Dentron Clipperton L , and it handles all that the amp can dish out. I'm tuning a pair of coaxial double bazookas so the match only needed a touch up for 1:1.

I'm not using it to tune chain link fences or paper clips so it works just great for me.

Purchased on ebay, for one third of the price of a "modern" tuner, it appears to have had very light use. I lightly lubricated the bearing surfaces and was good to go.

For good or ill, they don't build them like this anymore.