Bird Termaline 8892

[Rick K5IAR]

I was fortunate enough to snag the above load off eBay thanks to a hot tip from a cool guy.  This is my first foray into the world of Bird loads, so I need advice.  Do I have to use the suggested oil or is there a decent substitute? 

Most importantly, does anyone have an extra "vent" plug for this beast?  Not knowing the ins and outs of it I didn't ask if it came with one and it didn't.  It has the shipping plug installed.  There may be enough oil in it now for safe operation, I haven't looked closely.

Thanks,
Rick/K5IAR

[n2bc]

Manual online here:  http://www.bird-electronic.com/products/pdfs/opmanual/8890s.pdf

Shows the vent plug.  Also a section on coolant level.   You should be able to get the vent plug from Bird.

Nice hunk of equipment!

[WBear2GCR]

Mineral oil will work with some derating.

You can usually find a 5 gal bucket of bonafide "transformer oil" - better known as electric coolant oil - from your area's distributor of commercial oils & petroleum products.

Around here it's a Sunoco distributor, but the brand doesn't matter.

You can probably find the various types via the websites of the commercial petro product companies... maybe ur local club would go in on a bucket, which last time I checked was ~$30/5gals...

              _-_-bear

[Mike/W8BAC]

Hi Rick,

I use an 8890-315 here. It is the same as yours but sold with a different RF fitting (N) and the fan option. It has only one plug in the front for oil filling that, I assume, could hold a thermo switch or vent but mine is just a plug.

The load is rated at 2.5 KW by itself and 5 KW continuous duty cycle with the fan option. If the fan option is installed but not in operation the rating drops to 1.25 KW continuous. I have used this load at 1 KW plus for carrier, modulated 100% plus for extended periods without the fan running and the body of the load barely gets warm.

In my opinion I wouldn't even consider the thermo switch or a vent. Unless your running a 21-E at full throttle. You won't be using much of this load's potential. Since heat isn't a problem the vent is also unneeded.

I can't advise you on oil. Not knowing much on the subject I think I would trust the manufacturer. I have a cantenna I built in the 1970's with mineral oil but that's a cantenna and not an 8892. Oil's sometimes contain additives that could possibly harm your loads internals. Choose wisely.

Mike

[Rick K5IAR]

Thanks guys for the information and advice.  Mike, are you sure your's doesn't have another plug either on the top or side?  Mine has the large plug in the front for draining and filling, but also has the smaller plug on top for the shipping/vent plug.  I agree, I doubt I'd even heat this monster up very much at 1000 watts, especially since it would be only for a short time to load and test.  I will mostly be running it below 500 watts.  I'd sure hate to blow this monster up, however,  It's made like a battleship and I'm sure would pop like a brick of C-2 if it were heated enough.  I checked the oil level again and it appears to have the recommended amount.  It didn't look like it has been scorched, so I will likely leave that alone, at least for now.

Thanks again to all who responded.

Rick

[Mike/W8BAC]

Your right Rick. It dose have a VENT at the top front. I remember when it was shipped a bit of oil leaked from the vent due to tumbling along the way. I checked the level and found it very close to recommendation.

I was looking at my manual (same as the manual on line) and figured the vent went into one of the two plugs in front. It's been a few years since I even looked at it except to connect or disconnect it. You might consider a vent. A blown gasket wouldn't be fun.

Dose yours have two front plugs for a thermo switch and interlock switch?

Mike

[Rick K5IAR]

No, mine has only one front plug.  I wonder if it would work for those options if I ever wanted to add them?
Rick

[w1vtp]

I have the same unit except that it is a 30 dB attenuator.  One plug (I believe the red one - it is the flat one) is supposed to be used for shipping the unit so that the oil isn't accidentally leaked out.  The other one (the chrome one - it's longer than the shipping one) is a pressure relief fitting that is designed such that pressure built up during high power stimulation is allowed to bleed off. 

If you have the ship only plug then you should loosen it slightly (1/2 turn) during application of power.  It's worth the expense and effort to get the other plug.  Very nice unit.

Congrats, Al VTP