Uploaded July 2014 | Updated September 2026, 2 weeks ago
Instructional video on Repair and restoration of Amateur radio equipment . This Segment is on the Heathkit HW-99 four band 50 watt CW tranceiver produced in small numbers near the end of the Heathkit Company's life . Example shown Develops well over 50 watts on all bands and works well with good signal reports from other stations after repairs and alignment . Care must be taken adjusting the tiny coils it is VERY easy to break the tiny coil slugs . The slugs also get very loose in the coils if adjusted even a few times which these were. The slugs were sealed in place using candle wax to ensure they do not vibrate out of adjustment due to being so loose . It was necessary to remove two coils and screw the slugs out from the bottom of the coils then laying sewing thread in the hole in the center and screwing the slugs or coil cores back in gently then reinstalling the coil on the circuit board Adjusting these damaged coils WAS VERY difficult . While using the HW-9 it becomes apparent that you must adjust the output with the level control using an SWR/Wattmeter or similar the BAR graph power indicator is not accurate and it is possible to run to much output power possibly damaging the output transistor or final . I measured 80 watts out on 40 meters with the level control all the way up . A cooling fan blowing directly on the Heat sink is recommended . A 12 volt fan on a small plug in power supply or Wall Wart works fine . Soldering a one watt 100 ohm resistor in series with the Wall Wart will lower the voltage to the 12 volt fan and the result is a very quiet cooling fan that does the job well . Note in the video I am using a 24 volt fan with a 12 volt supply to achieve the same result . The 12 volt fans I am using like this came out of old computer power supplies . The end result of all this however is a fine working very simple basic CW rig fun to use and a rather rare heathkit.
Instructional video on Repair and restoration of Amateur radio equipment . This Segment is on the Heathkit HW-99 four band 50 watt CW tranceiver produced in small numbers near the end of the Heathkit Company's life . Example shown Develops well over 50 watts on all bands and works well with good signal reports from other stations after repairs and alignment . Care must be taken adjusting the tiny coils it is VERY easy to break the tiny coil slugs . The slugs also get very loose in the coils if adjusted even a few times which these were. The slugs were sealed in place using candle wax to ensure they do not vibrate out of adjustment due to being so loose . It was necessary to remove two coils and screw the slugs out from the bottom of the coils then laying sewing thread in the hole in the center and screwing the slugs or coil cores back in gently then reinstalling the coil on the circuit board Adjusting these damaged coils WAS VERY difficult . While using the HW-9 it becomes apparent that you must adjust the output with the level control using an SWR/Wattmeter or similar the BAR graph power indicator is not accurate and it is possible to run to much output power possibly damaging the output transistor or final . I measured 80 watts out on 40 meters with the level control all the way up . A cooling fan blowing directly on the Heat sink is recommended . A 12 volt fan on a small plug in power supply or Wall Wart works fine . Soldering a one watt 100 ohm resistor in series with the Wall Wart will lower the voltage to the 12 volt fan and the result is a very quiet cooling fan that does the job well . Note in the video I am using a 24 volt fan with a 12 volt supply to achieve the same result . The 12 volt fans I am using like this came out of old computer power supplies . The end result of all this however is a fine working very simple basic CW rig fun to use and a rather rare heathkit.
