Replacement blower for Henry 2k-4 desk console version?

[KF6CE]

I've got my Henry 2k-4 power supply all nice and quiet now that I had the the transformer and choke "dipped and baked" at a local motor rewinding shop. Now to find a quieter blower for the RF deck. Can anyone recommend a make and model?

This is the desk console model, so there is much less clearance available than the floor model.

73's

Sid

[K0BG]

How quiet do you want it to be? While there may be quieter blowers, most of them relate to less air flow. The 2K4 pushes the 3-500Zs fairly hard, so I don't think is would be advisable to lower the air flow. Perhaps Steve, WB2WIK, the resident Henry guru will chime in on this issue.

[W9GB]

Sid -

What blower did this Henry 2K-4 amplifier use ??

Some floor models use the Dayton 2C915 (140cfm) blower.
http://www.grainger.com/Grainger/DAY...e-Blower-2C915

w9gb

[KF6CE]

The blower in there now is a Howard Industries Model 1175-16-4065. The BOM just says it is a 115VAC 1600 RPM blower and the schematic seems to show it should be 115VAC - wired to the primary of a little transformer that is 115VAC (bias I think).

The key thing - is that it can be no wider than 4.5" from the face of the flange backward. So draw a line perpendicular to the flange and 4.5" is the max width before it hits the back plate. The blower in there now just barely fits.

I'll look at the Daytons for a 115VAC version. What I'd like to see is a dimension drawing - I'm sure it's there somewhere.

Of course I'd like to keep the airflow at spec. I have a floor model 2k-4 and it's a lot quieter than this one. I'm sure a newer design blower will be quieter yet.

Thanks for the pointers to the Daytons. Much appreciated.

Sid

[AH6RR]

I had a 2KD-5 that had a very loud bearing noise and I replaced it with a blower I got from Ameritron it is a EBM Papst G2S085-AA19-15 it fits with a little modification to the flange and is much quieter.

[KF6CE]

The EBM Papst blower G2S085-AA19-15 seems to be rated at only 26.5 CFM, a lot lower than the 140CFM's mentioned above. The Eimac data sheet says the tube, at full 500 watts of plate dis needs 13.0 CFM assuming a .082" of pressure (per tube). The 26.5 CFM spec is at 0 pressure.

[AH6RR]

The EBM Papst blower G2S085-AA19-15 seems to be rated at only 26.5 CFM, a lot lower than the 140CFM's mentioned above. The Eimac data sheet says the tube, at full 500 watts of plate dis needs 13.0 CFM assuming a .082" of pressure (per tube). The 26.5 CFM spec is at 0 pressure.

The EBM Papst blower worked just fine on my 2KD-5 it never got hot even in a RTTY contest and it too is a tight fit. You might get in touch with Radio Dan he sell's Henry amps and parts or can steer you in the correct direction.

[WB2WIK]

I've got my Henry 2k-4 power supply all nice and quiet now that I had the the transformer and choke "dipped and baked" at a local motor rewinding shop. Now to find a quieter blower for the RF deck. Can anyone recommend a make and model?

This is the desk console model, so there is much less clearance available than the floor model.

73's

Sid

I never thought any of them were loud, but I only use headphones and that blocks out the noise pretty well. I also use a highly directional microphone with enormous cancellation to the rear, and it's on a boom so an amp behind it can make lots of noise and the mike won't pick any of that up.

But in any case, one thing I did years ago when I had several monoband amplifiers all powered by a common power supply was to cool all of them with a remote blower. It was very quiet because it was very LARGE and wasn't high speed at all, I think only 1200 rpm. The blower was the kind used in home heating and air conditioning systems, and it was in a closet off the ham shack, with a grate ventilation grille installed in the bottom half of the door to allow air into the blower. The output of the blower went into a "box" made of aluminum about the same size as the big blower, and it had five 4" dryer hose outlets with flexible dryer hoses clamped to each one. The other ends of those hoses attached to mating fittings on the rear of the amps (4" ducts). It blew air through all five amps, whether they were turned on or not. A LOT of air, almost pushed the tubes out of their sockets; but it was eerily quiet, the only noise you could hear was the sound of rushing air coming out of the tops of the amps. No motor noise at all, since the motor was 15 feet away behind a door.

That worked very well and was a minimal investment, but does require "ductwork" in the form of inexpensive flexible dryer vent hoses.

[KF6CE]

Great story. I used to have a pair of Wilcox 96D1-A transmitters, one rigged for 40M and one for 20M as amplifiers. The blowers in those were large and a bit noticeable too.

And thanks AH6RR - the papst would probably do fine but I think the fit it prett tight as well. I'll track down Radio Dan and see what he has to offer.

So - here's my crazy idea - buy a big air compressor and put it outside and run air into the shack to cool the finals. OK - I did say it was crazy.

[WB2WIK]

Great story. I used to have a pair of Wilcox 96D1-A transmitters, one rigged for 40M and one for 20M as amplifiers. The blowers in those were large and a bit noticeable too.

And thanks AH6RR - the papst would probably do fine but I think the fit it prett tight as well. I'll track down Radio Dan and see what he has to offer.

So - here's my crazy idea - buy a big air compressor and put it outside and run air into the shack to cool the finals. OK - I did say it was crazy.

You don't need a compressor, just a blower. See my post, above. Heating/AC blowers are big and cheap and move a lot of volume. A compressor creates a lot of pressure, but not necessarily volume. You don't need pressure, you need volume.