MFJ 949E Help?

[KW4HKY]

My Elmer gave me one, said he can't figure it out. Same here. The manual is horrible. They calibrate in LETTERS and tell you how to tune in NUMBERS.

Meter will not light up without a 12V adaptor, or "removing cover and attaching 9V battery to connector". Pulled the case, no connector.

I found a wall wart and got the needle to back light, but having no luck tuning.

I searched youtube. One guys tried to tune, and gave up because the meter jumped all over the place.

One guy started a video on the tuner, but his rig died before he got there.

Is this thing good for the dummy load it claims it has, or just another More Fine Junk failure?

I'm using a mini GR5V and just trying to tune 10 meters, nothing way off band on the antenna range.

 

[Beetle]

Never heard of a "GR5V", but if you mean "G5RV", and you're only interested in 10 meters, start with the inductance as low as it allows (maybe on "A" or on "1", depending on which you have), and both capacitors at half-mesh. Go from there.

As far as the dummy load: disconnect the transmitter; switch to the dummy load position; connect your ohmmeter (you DO have one, right?) to the input and see if the meter reads somewhere around 50 ohms. I don't know how much power the OEM dummy load is rated, but it's probably quite easy to apply too much.

 

[WR0220]

I use the settings listed in the instructions as a starting point and fine tune from there.

http://www.mfjenterprises.com/pdffiles/MFJ-949E.pdf

If you can't get it to tune an acceptable SWR then it may not be functioning properly and need repair.

 

[hookedon6]

...Meter will not light up without a 12V adaptor, or "removing cover and attaching 9V battery to connector"...I'm using a mini GR5V and just trying to tune 10 meters, nothing way off band on the antenna range.

the ONLY reason 12 vdc is used is for the light.

a G5RV would not be my choice of antennas on 10 meters.

just LISTEN for the loudest signal (aka: a noise bridge) to rough tune the tuner. start with A-1 and rotate the "number" dial for a louder sig. when you get to A-10, then go to B-1,... ect .

there should be multiple settings that result in an acceptable VSWR. use the "lowest" dial (closest to A-1) settings possible.


BTW,..... you do have the meter in the "tuned" mode and not in the "bypass" position,.... right?

 

[FatHam]

the ONLY reason 12 vdc is used is for the light.

If it's anything like my MFJ-969, it DOES need the AC adapter to tune. I thought it was for the backlight only too, then fought tuning for close to an hour before someone asked if I'd plugged in the AC. Viola, it tuned my G5RV right up once I plugged it in.

 

[W5LZ]

Look at the schematic of that tuner. Is that DC connected in any way to anything besides the meter's light? If so, what is it powering? I've looked at that schematic and couldn't find anything powered except the lights.
- 'Doc

 

[Beetle]

If it's anything like my MFJ-969, it DOES need the AC adapter to tune. I thought it was for the backlight only too, then fought tuning for close to an hour before someone asked if I'd plugged in the AC. Viola, it tuned my G5RV right up once I plugged it in.

The instruction sheet for the 969 says in LARGE PRINT that the meter switch has to be ON for the meter to work. And that in turn implies that the AC adapter has to be plugged in.

 

[WR0220]

Look at the schematic of that tuner. Is that DC connected in any way to anything besides the meter's light? If so, what is it powering? I've looked at that schematic and couldn't find anything powered except the lights.
- 'Doc

Although the 969 requires power to operate, the 949 does not. The only thing the wall wart is for is to provide power for the lighting. I operate mine all the time without the wall wart plugged in and it works just fine.

 

[Blue Jay]

On the 969 the 12v is just for the meter lamp, (SW1A) SW1B compleats the circuit for the meter but NO 12V is needed for meter to work.

 

[hookedon6]

one more kick at the cat,...... a 949-E (aka: a DELUXE VERSA TUNER II) does NOT require 12 vdc to operate.

do you have the JUMPER wire connected?

is there ANY noise level change when you adjust the pots?,... if there is NO AF change, then open the thing up and check for broken connections/shorts to ground with a VOM.

have you tried to adjust it on 20 meters (where the G5RV was designed to operate)?

 

[WR0220]

On the 969 the 12v is just for the meter lamp, (SW1A) SW1B compleats the circuit for the meter but NO 12V is needed for meter to work.

Actually, the 969 does require power to measure PEP correctly. This is directly from the instruction sheet on page 1:

NOTE: The meter ON/OFF switch must be ON for the meter circuit to function. The MFJ-969 wattmeter circuit does not function accurately if the Auto Tuner in your radio is used. To disable the meter, turn the meter ON/OFF switch to the OFF position. Set the ANTENNA SELECTOR switch to one of the bypass positions when using the Auto Tuner in your radio.

The metering circuit in this unit provides very accurate forward peak power readings during with any form of modulation. Either an internal 9 volt battery for portable operation, or an external supply can be used to power the peak detector. Current demand is very low, and the 9 volt battery will last its' shelf life.

However, the OP has a 949 - not a 969 - so I stand by my previous post:

Although the 969 requires power to operate, the 949 does not. The only thing the wall wart is for is to provide power for the lighting. I operate mine all the time without the wall wart plugged in and it works just fine.