MFJ-969 ATU - a test by ZS1JHG The MFJ roller inductor antenna tuner that covers 160m to 6 m with powers up to 300 watts. A neat compact tuner with clear X needle SWR/Power meter. The case was opened and the variable capacitors and roller inductor seemed well made. The vane spacing of the capacitors is however close and I only tried up to 200 watts from an FT1000D which the MFJ-969 easily managed. The power output meter was over reading key down at 100 watts compared to my Bird 43 and I adjusted this on the pot in the RF sensing circuit board . (interestingly marked MFJ 986). The roller inductor takes some adjusting to get your SWR down even though I made up a table for the main harmonic bands. A dedicated ham bands ATU by one of the big three was quicker to tune up in comparison. The roller inductors movement was not as smooth as its bigger brothers even though I tried special nylon gear lube but acceptable. The face panel was well laid out and clearly marked with good clearance between the rather small loading knobs. After some use it was noted that the roller inductor developed some black soot on its air coil and this required cleaning to restore proper operation, at all times less than 100W was used on 40m to 10m. I tried the ATU with an end fed wire and the built in balun did its job only getting slightly warm at 50W key down for a

Mfj 969 Atu Test by Zs1jhg

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Looking for an ATU for your antenna , ZS1JHG puts the roller inductor MFJ 969 ATU to the test.

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MFJ-969 ATU - a test by ZS1JHG

The MFJ roller inductor antenna tuner that covers 160m to 6 m with powers up to 300 watts.

A neat compact tuner with clear X needle SWR/Power meter. The case was opened and the variable capacitors and roller inductor seemed well made.The vane spacing of the capacitors is however close and I only tried up to 200 watts from an FT1000D which the MFJ-969 easily managed. The power output meter was over reading key down at 100 watts compared to my Bird 43 and I adjusted this on the pot in the RF sensing circuit board .(interestingly marked MFJ 986).The roller inductor takes some adjusting to get your SWR down even though I made up a table for the main harmonic bands. A dedicated ham bands ATU by one of the big three was quicker to tune up in comparison.The roller inductors movement was not as smooth as its bigger brothers even though I tried special nylon gear lube but acceptable.The face panel was well laid out and clearly marked with good clearance between the rather small loading knobs.After some use it was noted that the roller inductor developed some black soot on its air coil and this required cleaning to restore proper operation, at all times less than 100W was used on 40m to 10m.I tried the ATU with an end fed wire and the built in balun did its job only getting slightly warm at 50W key down for a period.At the price of the MFJ-969 auto ATU`s are now available at the 200W level and I would be inclined to look at these rather.