Review: Magni Monitor MM-400

THIS IS A PRELIMINARY CRITICAL EVALUATION OF THE MAGNI MONITOR MM-400 WAVEFORM & VECTORSCOPE COMBINATION done Nov. 1991. It does not pretend to be complete, infallible or to mention all of the unit's features. It is intended to highlight notable findings or thoughts that came to mind when I was testing it. More thorough reports than this can be commissioned on a paid product evaluation basis. These comments are copyright & may not be used in any publication or for advertising without written permission.

*While the display is not nearly the detail & resolution you would expect from a much more expensive scope with a tube built in, it is adequate for video production & even good enough to calibrate some types of equipment. It's advantages are size, cost & ease of placement.

*It is not possible to display the waveform & vectorscope at the same time. You should be able to display a smaller version of each display on the same screen at the same time like you can with the Hamlet Video HVI301. It would be very handy to have a separate BNC output for the waveform & vectorscope so you could view them on separate screens.

*It should come with 4 BNC 75 ohm terminators. A one foot BNC cable for looping to ext. reference should also be provided.

*Corners of the unit are very sharp. It can cut your skin or scratch your furniture very easily.

*A strange type of Phillips screw is used on the side of the unit making it very difficult to open.

*If desired, the unit can be recessed by changing the mounting brackets.

*IRE pedestal adjustment with dial is 12 increments per 10 IRE. It would be nice if they were a bit finer.

*Vector targets just have a dot which is difficult to see rather than a +-2 degrees box.

*Every time you switch back from vectorscope to waveform, the zero baseline takes a moment before it rises & stays put. I found that I was constantly adjusting for zero level & that I would frequently make a misreading because it had drifted. It really needs some sort of DC stabilizer (DC restore clamp).

*Not much heat was generated by the unit & it didn't even need a fan. Signal measurement seemed to be very stable regardless of the temperature of the room or the Magni unit.

*On the waveform you cannot select for a parade of just 2 (flat & low pass). You have to have a narrow parade of 3 with chroma differential (chromapass).

*On parade of filters the zero baseline of display goes down at the right with respect to the gradicule & other 2 displays.

*The white plastic wire clip on back of remote box breaks easily.

*This unit does not handle Y/C in loop through mode. For the life of me, I can't figure out why some manufacturers haven't included this important feature in an inexpensive scope like this. It has been 4 years since Y/C equipment first hit the market. This scope will do component & composite but not Y/C. The manual does mention that you could use a breakout cable & self terminate the luma on one BNC & the chroma on the other loop through BNC, however this does not work satisfactorily on all Y/C devices & it does not allow you to pass the signal along to your recorder. The Y/C self termination worked fine from my Omni-Gen 711 genlock/encoder/keyer, caused a 4 IRE luma rise from my Hitachi C1 broadcast camera, and caused the whole scope image to go totally crazy from my Hotronics AH91 TBC.

*There is no on/off switch. The unit probably doesn't draw much power & doesn't create much heat but I would still prefer to turn it off.

*Alarm is on the LCD display only, so I presume that the alarm doesn't work if you decide to use a monitor for the display.

*You can switch from crystal lock to VCR lock for a more stable reading if you're scoping a signal direct from a VCR without a TBC.

*There is no built in method of checking calibration. You have to order an option to be able to do that.

*The 0 & 100 IRE lines of the gradicule should be a different color than the other lines so you can easily see at a glance if the levels are outside legal limits.

*There are plenty of menu choices & fortunately you do not have to go into the menu for the most used features such as switching between parade & regular.

Yours truly,

Doug Hembruff  
RevC Jan20/92