[Hallicrafters] SR 2000


Jim Liles hallicrafterssr2000 at k9axn.com
Mon Jul 28 22:35:57 EDT 2014


Hello again Donato:

How much power out can you get from the radio in low and high power mode with 15 ma of screen current?

After tuning the radio for maximum 15ma of screen current, further increases in transmit RF drive should cause the anode current to drop.  What do you observe when you do that?

Kindest regards Jim K9AXN 


-----Original Message----- 
From: Donato Mascia 
Sent: Monday, July 28, 2014 5:39 PM 
To: Hallicrafters at mailman.qth.net 
Subject: [Hallicrafters] SR 2000 

Hallicrafters SR 2000 (serial No. 452000 142001), good conditions + power
supply P 2000.
Low voltage power supply tuning position for approximately 1800 volts. At
the end of tuning by going to the location HT, about 2800 volts read on the
instrument of P 2000, instead of increasing the anode current is lowered
circa 20-40 mA, and a similar reduction also the output power (about 450
watts according in position low voltage is passed to about 300 watts and
less in position HT). Even the plate voltage drops from 2800 to about 2500
- 2600 while the voltage of the screen grid appears normal and stable
300-volt low-voltage and high-voltage 400 volts. Change both 8122 and the
driver no change. Other voltages and currents all normal. At the receiver
nothing to report. Only resistor R 316 on P 2000 (12 kOhm Nominal 25 W) is
about 45 kOhm. Replaced by one with the correct value 12 kOhm no change.
The grid current without signal is sharply negative and goes up to about
10-15 mA with the signal. The rest all normal, proper the bias. Antenna OK.
Could I have some advice for the anomaly ? Perhaps the diodes of the HT ? I
thank you for your kindness and competence to restore the noble and
venerable apparatus.

IZ5URV (former I5MVD) Donato Mascia.
______________________________________________________________
Hallicrafters mailing list
Home: http://mailman.qth.net/mailman/listinfo/hallicrafters
Help: http://mailman.qth.net/mmfaq.htm
Post: mailto:Hallicrafters at mailman.qth.net

List Administrator: Duane Fischer, W8DBF
** For Assistance: dfischer at usol.com **


This list hosted by: http://www.qsl.net
Please help support this email list: http://www.qsl.net/donate.html


More information about the Hallicrafters mailing list
This page last updated 19 Mar 2024.