Dealing with the Overheated and Cracked R232 - Revision history

Gordonp at 20:29, 11 November 2020

2020-11-11T20:29:15Z

← Older revision		Revision as of 20:29, 11 November 2020
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	Awesome new 10-ohm 20W R232! This Ohmite replacement brings higher-dissipation, and solid mounting.		Awesome new 10-ohm 20W R232! This Ohmite replacement brings higher-dissipation, and solid mounting.

	I wanted to mount R232 very solidly, so I opted for a tubular-ceramic resistor with mount-clips. I also moved to higher-dissipation capacity (20W) than Collins specified (14W), and I chose a new placement with improved air circulation and reduced heat-soak of nearby components - along the edge of the Relay Shelf.		I wanted to mount R232 very solidly, so I opted for a tubular-ceramic resistor with mount-clips. I also moved to higher-dissipation capacity (20W) than Collins specified (14W), and I chose a new placement with improved air circulation and reduced heat-soak of nearby components - along the edge of the Relay Shelf.

Gordonp at 20:28, 11 November 2020

2020-11-11T20:28:53Z

← Older revision		Revision as of 20:28, 11 November 2020
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	The purpose of this resistor is to limit screen-supply (inrush) current, in the same manner as R222 and R223 do for the HV plate-supply.		The purpose of this resistor is to limit screen-supply (inrush) current, in the same manner as R222 and R223 do for the HV plate-supply.

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Gordonp: Created page with "
left R232 broken into two pieces. Somewhere along the line, a previous repair has replaced the Collins 10-ohm 14W resi..."

2020-11-11T20:28:30Z

Created page with " 500px|thumb|left R232 broken into two pieces. Somewhere along the line, a previous repair has replaced the Collins 10-ohm 14W resi..."

New page

[[File:Cooked_broken_r232.jpg|500px|thumb|left]]

R232 broken into two pieces.
Somewhere along the line, a previous repair has replaced the Collins 10-ohm 14W resistor with this small (2W???) resistor; it's overheated then cracked as a result.

The purpose of this resistor is to limit screen-supply (inrush) current, in the same manner as R222 and R223 do for the HV plate-supply.



[[File:30s_1_r232_tubular_ceramic_replacement.jpg|500px|thumb|right]]

Awesome new 10-ohm 20W R232! This Ohmite replacement brings higher-dissipation, and solid mounting.
I wanted to mount R232 very solidly, so I opted for a tubular-ceramic resistor with mount-clips. I also moved to higher-dissipation capacity (20W) than Collins specified (14W), and I chose a new placement with improved air circulation and reduced heat-soak of nearby components - along the edge of the Relay Shelf.

Mounting hardware is all 18-8 stainless: #6-32 x 3/8 Phillips pan-head machine-screws, internal-tooth lockwashers and hex-nuts. On the outer (visible) edge of the Relay Shelf, I aligned the Phillips-head crosses :-)

In this location, and for other repairs, my wire of choice is either 22ga or 18ga (19 or 34 strands of 0.007 for maximum flexibility), with 3kV silicone insulation.

Dealing with the Overheated and Cracked R232 - Revision history

Gordonp at 20:29, 11 November 2020

Gordonp at 20:28, 11 November 2020

Gordonp: Created page with " left R232 broken into two pieces. Somewhere along the line, a previous repair has replaced the Collins 10-ohm 14W resi..."

Gordonp: Created page with "
left R232 broken into two pieces. Somewhere along the line, a previous repair has replaced the Collins 10-ohm 14W resi..."