[Heathkit] HW-16 & HG-10B

[W5VPU at aol.com]

Hello everybody.
 
Need some help, please. Recently acquired two HW-16 & HG-10B at an  estate 
sale. I am new to these rigs. When I plug the VFO into the HW-16, I get a  very 
sensitive receiver on either "Standby" or "Spot." However, when I switch to  
"Send" there is an incredible buzz in the receive audio. Does put out about 70  
watts through a tuner into antenna or dummy load. However, the "Buzz" never 
goes  away on receive. 
 
I've looked through "Troubleshooting" section in Manual and find nothing.  
Looked through reflector at subjects only and read the HW-16 posts for past  
year and did not find any note addressing this problem. Don't have any  crystals 
to test wthout VFO attached. Any suggestions for "diagnosis" and  possible 
"treatment" options for this malady? Thanks loads.
 
Raymond