Re: Panasonic has a 1200W microwave oven in Wallyworld with 'inverter' technology

[w4bfs]

well, I wanted to resurrect this old thread http://amfone.net/Amforum/index.php?topic=35604.0;topicseen to see iffin there is any new info ....

thanks to all who have responded .... thanks for the sckizmatic, Phil .... thanks for the Utoob links and other legwork

I bought one of these offin the Ebay general sto ... looks promising, maybe for parts

for ham radio application looks like bridge drive (H topology) and full wave rectification would yield a 2 kV supply at 500 mA or so .... this is not my area of expertise but I need a way to build hv supplies that don't weigh so much

[PD0RTT]

If you want to try some inverter technology, try to construct and designing a high voltage switched mode power supply:

http://w5jgv.com/hv-ps1/

Martin

[flintstone mop]

I accidentally bought an inverter type oven for my parents about 6 yrs ago...Are they hard to find?? It was 1000 watts and was the lightest oven I ever picked up.
Why are they still using heavy old transformers?

[Opcom]

The microwave oven transformer, diode, and cap is still much cheaper and even more reliable than a fancy inverter and MOSFETs and high tech stuff.

I bought a Panasonic inverter oven. Cost a lot of money and it was not long before the inverter blew up. It was out of warranty of course.

[MikeKE0ZUinkcmo]

I also bought a Panasonic "inverter" probably 5 or 6 years ago at least, and its been great.

Now of course, tomorrow I'll be back at Best Buy looking for it's replacement.

[KA2DZT]

Well, as is usually the case...

I bought a Panasonic "inverter" probably 5 or 6 years ago at least, and nary a problem...

Now of course, come tomorrow I'll be back at Best Buy looking for it's replacement.

Mike

Knock on some wood and you should be OK.

Fred

PS Make sure it's real wood.

[w4bfs]

If you want to try some inverter technology, try to construct and designing a high voltage switched mode power supply:

http://w5jgv.com/hv-ps1/

Martin

thanks Martin ...taking a good look at this ...73 ...John

[WA2SQQ]

Hey guys - thanks for all the positive feedback on the Panasonic MWO's
I'm a Sr Product Engineer @ Panasonic, for another product. One of my co-workers (W2CET) is the Product Engineer for the oven's. When this topic first came up we reached out to one of our engineers (also a ham) in Japan to see what he though about using the inverter power supplies for amateur applications. His response is below ...

As for Use of  MWO inverter power supply for 1kW Linear amp use,  I doubt.
Since the output power (voltage) of our inverter itself is very unstable.
With no magnetron oscillation, No load, and no MWO control PCB, I measured myself and found upto around 7kV P-P. Once magnetron start oscillates its down to about nearly stable 4 kV, and the Magnetron tube itself’s  function/charactrstic as Zenner. The output current wise controled by control PCB, PWM control and maximum of around 300mA with forced air cooling required and limited time only.

"This area, when I was speaking engineer, but so much complicated. As you know, microwave oven output specification wise states by IEC power measurement, not RMS power. IEC standard bases,  the maximum output power can keep only about first minute operation. But when no control signal/power, I am not sure how long we can pulled out power. In any case, maximum power we can get is about 4kV x 0.3A = 1.2kW only.
So I think it is not enough power for Good linear isn’t it?"

[w4bfs]

Hey guys - thanks for all the positive feedback on the Panasonic MWO's
I'm a Sr Product Engineer @ Panasonic, for another product. One of my co-workers (W2CET) is the Product Engineer for the oven's. When this topic first came up we reached out to one of our engineers (also a ham) in Japan to see what he though about using the inverter power supplies for amateur applications. His response is below ...

As for Use of  MWO inverter power supply for 1kW Linear amp use,  I doubt.
Since the output power (voltage) of our inverter itself is very unstable.
With no magnetron oscillation, No load, and no MWO control PCB, I measured myself and found upto around 7kV P-P. Once magnetron start oscillates its down to about nearly stable 4 kV, and the Magnetron tube itself’s  function/charactrstic as Zenner. The output current wise controled by control PCB, PWM control and maximum of around 300mA with forced air cooling required and limited time only.

"This area, when I was speaking engineer, but so much complicated. As you know, microwave oven output specification wise states by IEC power measurement, not RMS power. IEC standard bases,  the maximum output power can keep only about first minute operation. But when no control signal/power, I am not sure how long we can pulled out power. In any case, maximum power we can get is about 4kV x 0.3A = 1.2kW only.
So I think it is not enough power for Good linear isn’t it?"

yes ... the power supply appears to be highly specialized to the application .... the flyback transformer is interesting and I am considering repurposing it to a bridge driven input - bridge rectification output choke input filter .... it would be interesting to know a few specifications of the transformer and if this component is available, stand alone ...thanks ... John

[WA2SQQ]

Let me know what part, from what model and I'll see what i can come up with.

[w4bfs]

wow .... coming up with a model number is tough .... pbf on the circuit board.... single primary switch and a .28 uFd resonating capacitor .... good component id screening and I see several high voltage warnings written in pictographs ...let me know iffn you need more

[WA2SQQ]

No,  meant the model of the oven, so I can get the service manual

[w4bfs]

awkward .... I bought just the supply off of Epay ....don't know for sure the oven model number

16 aug 15 - got this model number of Epay ad: Panasonic F66459X91AP ...looks like the one I got

[WA2SQQ]

Ran that number through several databases and came up empty. Can you post a few photos? I'll do my best