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[Amps] Replacing meter bulbs in Command Tech HF-2500

To: amps@contesting.com
Subject: [Amps] Replacing meter bulbs in Command Tech HF-2500
From: ki7m@comcast.net
Date: Mon, 19 Jan 2015 19:46:19 +0000 (UTC)
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I'd like to share an email I got from W3PAL concerning the this:  
  
I think you will need to remove the transformer. 
To gain access to the Switch Board, remove both top and bottom covers and then 
remove the 4 stainless screws and bolts that hold the transformer. Unclip the 
transformer Molex connector and remove the transformer unit. Take care as 
towards the front of the transformer there is a small disc capacitor connected 
on the chassis which could easily be crushed by the heavy transformer. 
Now you can work without hindrance. 
Take the knob off the IP/VP switch – it’s held in with 2 small grub screws. 
Unscrew the fine nut which holds the switch in place, and slide the switch out. 
The switch is hardwired to the board, so the switch and whole board will now 
come out as a single unit. 
You’ll notice 4 small ‘Festoon’ type bulbs. They look like fuses but are not 
and work differently. 

Keep in mind that most circuits in this amp were designed very poorly. 
Documentation is terrible and not consistent with each amp. Servicing this amp 
can be a pure nightmare. 
The 12VDC voltage regulator on the control board is only rated for 1A. The four 
original bulbs draw 0.25A each. It's 1A for the light bulbs only. Everything 
else overloads the regulator. They often fail because of this. 
It's best to use 6615F bulbs that draw only 0.08A each. You can also try to 
replace it with newer LED bulbs. Just google: festoon Sun Visor LED bulbs. Just 
make sure that all four new LEDs don't draw more than 1/2A. I would add a small 
capacitor across each LED bulb's terminals to eliminate any induced RF. 
Good Luck. 
de W3PAL 

Thanks to Ivanov for that replay. While I may disagree with his assessment of 
the design of the amp his info seems accurate and to the point. 
  
Terry, KI7M 
  
  
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