View and Download AMERITRON ALH instruction manual online. HF POWER LINEAR AMPLIFIER. ALH Amplifier pdf manual download. Manuals and User Guides for AMERITRON ALH. We have 1 AMERITRON ALH manual available for free PDF download: Instruction Manual. Download AMERITRON ALH 1,,5MHZ LINEAR AMPLIFIER SM service manual & repair info for electronics experts.
I don’t know if there is even a “service” manual available for the ALH.
The suppression of the third- order harmonic is the difference between marker 3D and 4D. In reality, no way to predict how the circuits actually behave.
The energy could not leave via the high manuaal of the plate circuitand so chose the shortest path via the tube. Given its damage in the depicted tubeI think it’s caused by parasitic oscillationswhich led to a high voltage.
Please note that the output in the table is partly achieved by exceeding the maximum grid and anode current. The Ameritron amps I’ve seen aren’t poorly made. I don’t know what they were thinking.
Flashover in a tube of an unprotected RF amplifier. The Grid current meter was reading on transmit with no drive.
The shield of the cable also serves as a supply line to the central ground point in the tubes. The AL- H is sold worldwide and is quite a well-built “budget” amplifierbut by no means easy to repair. After each modification the amplifier was firmly tested and manhal never becames red.
I’m guessing it was designed at the Christmas party and they were all drunk. Not close to L4 but far away on the PSU board. K9STHAug 2, What a horrible linear amplifier! Therefore, a sumiere test was done with the two types. I’ve never seen one before. Your name or email address: The PA had no additional protection and had not been operational for years. However, it’s as if the Valves are getting no drive on Transmit. Irregularities in the schematic. AF6LJAug 1, A tentative conclusion is that this AL – H does not distort the signal of the drive stage.
I am wondering why you say the amp is awfully made. On the other bandthe SWR will be high and is an internal tuner required for full ouput. The size of the 10 m coil has become too small due to mounting method.
AMERITRON AL-811H Manuals
This is a later model, by the way. Hopefully it didn’t smoke the meter Register for a free QRZ account. With this methodthe distance between S1 and C26 changed to a small capacitance in parallel with the load capacitor and the total inductance of the coil 10 m is thereby reduced. You must log in or sign up to reply here. Connect the amplifier to a dummy load and adjust for maximum ouput. I wouldn’t supersize that diode, it is a weak link for a reason as I understand it.
I haven’t confirmed this yet, as it’s really hard to get at the main board to test anything! The shielding of the cable is only grounded at the side of C Any suggestions would be welcome. Yah bigger is better. My inspection yielded a burned grid resistor and a partially conductive varistor on.
Roger, you must be the only person in your area that is willing to tackle ham amplifiers with problems. I assume there are no professional repair people around. No the meters are both OK.
Because there size s little space was to the valve sockets. I think it had a Valve flashover before I got it. My preference would be given to the latter because I have more experience with it. I used as “earth” the screw at the bottom of the anode choke. Amerittron was not the diode I was thinking of.