Call Search
     

New to Ham Radio?
My Profile

Community
Articles
Forums
News
Reviews
Friends Remembered
Strays
Survey Question

Operating
Contesting
DX Cluster Spots
Propagation

Resources
Calendar
Classifieds
Ham Exams
Ham Links
List Archives
News Articles
Product Reviews
QSL Managers

Site Info
eHam Help (FAQ)
Support the site
The eHam Team
Advertising Info
Vision Statement
About eHam.net

donate to eham
   Home   Help Search  
Pages: [1]   Go Down
  Print  
Author Topic: Amplifier Cabinet/Chassis  (Read 1838 times)
W7WRJ
Member

Posts: 14




Ignore
« on: June 16, 2017, 05:34:49 AM »

Does anyone know where I can find a Cabinet/Chassis that could be used to build a 2xGS-35b amplifier?  I'm looking for an enclosure that is about 10 inches high,  15 inches deep and 17 inches wide.  This enclosure will only house the RF deck, I already have a separate enclosure for the power supply.  I would prefer a new enclosure, but am ok with a used one also same from a gutted amp.

Thanks,

Mike Chasse
W7WRJ
www.qrz.com/db/w7wrj
Logged
KC4ZGP
Member

Posts: 1637




Ignore
« Reply #1 on: June 16, 2017, 09:33:34 AM »


Mouser, Digi-Key. Heck even a drawer from an abandoned filing cabinet will do. I did same for my 160 meter
T-matcher. And I used a small cash box for an earlier T-match.

If you don't mind the hoakiness. You're the only one who has to look at it.
No one cares what the amplifier looks like. How it sounds on the air is what matters.

Use a whole file cabinet. In drawer number one the power supply, drawer number two the amplifier and in
drawer number three important tax papers and old Spanish coins.

And for a good laugh, you could have spring-loaded snakes in each drawer to scare folks who look inside things that are
none of their business.

Have fun.

_ _ ... ... _ _

Kraus



Logged
N3QE
Member

Posts: 4885




Ignore
« Reply #2 on: June 16, 2017, 09:55:21 AM »

Aluminum angle for a frame, and solid and/or performated sheets attached to the angle every inch or so. At least two sides (bottom and front) will often be solid 1/8" aluminum, but the other sides can be thinner or perforated metal.

If you can weld the aluminum frame at the corners, even better.
Logged
K0UA
Member

Posts: 1380




Ignore
« Reply #3 on: June 16, 2017, 10:30:31 AM »

Aluminum angle for a frame, and solid and/or performated sheets attached to the angle every inch or so. At least two sides (bottom and front) will often be solid 1/8" aluminum, but the other sides can be thinner or perforated metal.

If you can weld the aluminum frame at the corners, even better.


Hey now, you are getting into TIG territory, or at least a MIG with a spoolgun.
Logged
N8CBX
Member

Posts: 478




Ignore
« Reply #4 on: June 16, 2017, 10:37:27 AM »

...enclosure that is about 10 inches high,  15 inches deep and 17 inches wide.
I would add about 2" or more to the height. Just the tube is 7" in length, and I'm assuming the tubes are vertically mounted?
Jan N8CBX
Logged

Dayton Ohio - The Birthplace of Aviation
DL8OV
Member

Posts: 761




Ignore
« Reply #5 on: June 16, 2017, 10:41:58 AM »

Kraus has the right idea. many years ago I built a tube linear into a two-drawer filing cabinet, the HV supply was in the bottom drawer and the RF deck was in the top. Lots of space, good thick steel (it was old), and after I added brass finger stock to the seams it was RF tight.

Just remember some safety interlocks!

Peter DL8OV
Logged
K8AXW
Member

Posts: 6317




Ignore
« Reply #6 on: June 16, 2017, 06:26:47 PM »

When I built my amp I used sheet aluminum in which I had drilled vent holes.  I first created a drill guide pattern with sheet steel.  I clamped it to the sheet aluminum, drilled two holes and then used bolts to hold the pattern in place while I drilled the remaining holes (using a 1/8" drill for a pilot hole and then a 1/4" drill bit for the final vent hole)

After finishing an area of the panel I deburred it on both sides with a larger bit.  After the two side panels, rear panel and the top panels were completed I tied them together using 1/2" aluminum angle bought at ACE Hardware.  I used pop rivets to hold all of it together.  (The front panel had no vent holes because this is where the control shafts were located.)

The top was attached using #6 sheet metal screws so I could remove the top when I needed to.

This assembly was attached to a large chassis in and on which everything else was put.

Final count, including the initial pilot holes was just a little over 6,000 holes!  It took a week of very careful work but it was worth it.  This was back before quality perf aluminum was available.

The final result was a strong RF cage and the finished product looked pretty good, especially after rattle-can spray painting it with high-temp flat black.  (All mating surfaces were NOT painted.)

My article and some photos at the end will give you an idea on what this thing looks like:  http://www.arrl.org/news/build-your-dream

I'm showing this to maybe give you an idea or two.  Good luck, take your time and have fun!

Logged
WA7PRC
Member

Posts: 1838


WWW

Ignore
« Reply #7 on: June 16, 2017, 10:17:09 PM »

A single GS35b can dissipate 1500W (some say more). For ham use, one is plenty.
To build a 160m amplifier using a single GS35b, I bought a Heathkit SB220 cabinet:

It is 14-7/8"W x 8-1/4"H x 14-1/2"D. In order to maintain the Heathkit appearance, I'll use HK knobs,
switches, and meters. I'll use the GS35b "socket" designed by the late Tony King W4ZT:

It minimizes grid-ground reactance, airflow resistance, and above-chassis height.

The HV transformer I rewound...

...will fit in the separate enclosure I made from sheet aluminum + angle stock:


vy 73,
Bryan WA7PRC
Logged
KD6VXI
Member

Posts: 161




Ignore
« Reply #8 on: June 17, 2017, 10:21:03 AM »

ICA Manufacturing.

They sell them in multiple sizes, and you can get them prepunched.

It's where all the cool people shop lol.  Seriously, though.  Great place for chassis, and they hold up to the CBers in their mobiles, too.  Quality metal.

--Shane
KD6VXI
Logged
KM1H
Member

Posts: 2508




Ignore
« Reply #9 on: June 19, 2017, 05:29:13 PM »

There are many choices on Fleabay, hamfests, etc using old Hallicrafters TX, RX, and amp cabinets. The HT-32 and HT-33 families, SX-28, SX-42, SX-62/62A are some examples that all use a standard 19" rack panel and are rugged steel with flip tops and excellent ventilation plus enough room to include the PS if your up to heavy lifting back when men were still men Roll Eyes Grin

The are other similar generic cabinets used for various Collins, Hammarlund, National, and others using a 19" standard size rack panel.

Carl
Logged
K1HMS
Member

Posts: 463




Ignore
« Reply #10 on: June 19, 2017, 06:39:26 PM »

For prototypes that will be deivered to a customer we use http://www.protocase.com

They will make it to your drawing, all connector holes, powder coat or paint, etched or silk screened logos - model numbers - knob labels, and deliver in 3 days. We recently did a 19" rack mount x 3" deep for a GPS synchronizer. It was around $250 but looked professional. To keep the price low we started with one of their exsisting designs with with our connector, meter, and contol holes, and their basic paint and silk screen.

I realize you are likely looking for a surplus chassis for next to nothing, but if you want something sharp protocase does a good job. One thought is to just use them for a flat front panel with labels.

Years ago I picked up a non functioning Hewlett Packard boat anchor, gutted it, and used the case. Thier cases from the 70s are a bunch of standard rails, flat panels,  and sheet metal covers making them easy to repurpose.

73
Logged
WA7PRC
Member

Posts: 1838


WWW

Ignore
« Reply #11 on: June 19, 2017, 06:39:56 PM »

I traded a few emails with Mike. He's made a decision.
Logged
Pages: [1]   Go Up
  Print  
 
Jump to:  

Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC Valid XHTML 1.0! Valid CSS!