Sharp Convection Microwave Oven - Hatteras 39SX - Fuses in Power Supply?

[av8torrich]

Hello:

This weekend the Sharp convection microwave oven in my vessel stopped working. This is the original oven which came with the vessel when new. Based on how it failed, I suspect it is a power supply problem.

The question is, has anyone opened one of these up? If so, was there a fuse located near the AC input to the Power Supply Board? If there is, then I think it might be worth taking it apart and repairing it instead of replacing the whole oven.

Rich

[Blaine Thorpe]

Haven't had one apart, but we are pulling a working unit out of a 1992 43C. Yours for the cost of shipping from Illinois.

[av8torrich]

Hi Blaine:

I have been watching some youtube video's on the topic. It appears there are a great many microwaves which the AC input is fused. When I run down to the boat next weekend, I will take it apart. if the fuse is not the issue I will certainly take you up on this offer.

Thanks for responding to this post!

Rich

[av8torrich]

Hi Blaine:

I am leaving you a PM with regards to the Microwave you are pulling out.

For everyone elses benfit, there is a 250V 20A Buss fuse located right in line with the AC power cord. Unfortunatly for me, while the fuse was blown, the problem appears to be deeper (bad magnetron).

Rich

[Blaine Thorpe]

This is the one that I am removing. The rough dimensions are 30" wide, 16" high, 15" deep. I'll get the model number early next week.

[Blaine Thorpe]

I found a photo of the ID tag on the microwave.

[av8torrich]

Hi Blaine:

i really appreciate you taking the time to obtain photo's of your Sharp. After comparing the dimensions, I am afraid this model will be too large to fit on my 39SX. As a matter of fact, I am going to have to dissasemble the R-7A95 to get it through the cabin door, and onto the bridge.

I guess it may be time to see about sourcing some parts, and repairing the High Voltage/Magnetron section of the unit.

Thanks Again!

Rich

[dottieshusband]

Don't know how far you got into it, but replacing the magnetron is a 2 on the DIY scale. Most of the microwaves have common magnetrons and they aren't that expensive, $75 buck range. I've also had cracks develop in the printed circuit boards..and you can jump around them... But the bottom line is, microwaves are cheap and easy, finding the right size..not so much!

[dottieshusband]

FYI, a new magnetron for the r1821 is $40 bucks on eBay. http://www.ebay.com/itm/Sharp-Microwave-Magnetron-Tube-RV-MZA093WRE0-/201314799638?hash=item2edf4c1016:g:sloAAOSwv0tVED3 H

[av8torrich]

The R-1821 is a working model on Blaine' s Vessel. I have found a replacement for the R-7A95 . After review the only one I am able to find is around $118.00 from a well known parts distributor. Sears still has them, but they will not sell them to the general public, because they insist a technician do the job.

I will bring the soldering station, and High Voltage Probe/Divider down and check to make double sure I do not have a HV oil filled capacitor problem, or half wave bridge rectifier on the fritz.

You are right about the size issue. I am not sure how they got this thing into the vessel in one piece. The only way I can see is if they installed it before the cabin was closed off. Of course, they could have dismantled the chassis in brought it in, but this does not make much sense to me.

Rich

[Avenger]

Just be aware... a friend of mine worked as an appliance repairman for Sears and took a bad hit from a microwave oven he was working on. Ended up in the hospital for several days and about six months to fully recover. Be careful.

[av8torrich]

This is good advice. I am qualified, and used to working around High Voltage Circuits. The voltages associated with the B+ side (I think Magnetrons use HV supplied to the Filaments) are LETHAL. As we talk about the possibilty of repair on this thread, it does seem like a trivial task, but you must really have a firm understanding electrical safety when dealing with these types of power supplies.

Thanks for pointing this out!

Rich

[dottieshusband]

$73 bucks for the r-7a95, from these folks https://www.encompassparts.com/item/8133719/Sharp/RV-MZA377WRZZ/Magnetron

[av8torrich]

Wow! That is a good find! Thanks for the link...

Rich