AMERITRON AL-1500 AMP... This amp was built by Ameritron in Toledo - not MFJ (good). It is fully upgraded with brand new boards from CTR Engineering (W8JI). He is the original designer of the amp. There are three upgraded boards: Filter Cap board, Rectifier board & Start-Step board. The amp has not been on the air since the upgrades were installed. In other words, most of the circuitry in this amp is brand new.
The amp was not purchased new and has an early serial number of 788. I don't know its history but it is very clean. It came with a soft tube that eventually failed though I did not run it hard. This lead me to investigate the VHF parasitic suppression kits then offered by Rich Measures, AG6K (now SK). This kit is also installed and they are no longer available. But FYI, there has been considerable debate over whether tube damage from VHF parasitics is a real thing. There was this hissy fight on-line between Measures and the amp's designer (W8JI) where both behaved like children. W8JI says there is no parasitic problem and the kit has no benefit. Measures says it protects the tube and bandswitch, and also makes the amp tune more easily (which I attest to). Nobody says it does harm. There is a QST article and a rebuttal. The AG6K information is still on-line. Do your own reading. Not many of these amp have the VHF protection. https://www.qsl.net/w/wa5bxo/ag6k/ Also, I've replaced the tube with an Eimac 3CPX1500A7 which is an MRI pull. To check the tube and all the upgrades I brought the amp to Dallas for testing at the Array Solutions / WX0B amp lab. Jay ran the tests with his big dummy load on 40m. Tube outputs 1500w easy at 53w of drive and only 20ma of grid current. This is the way you want to run it for long tube life. We pushed the envelope and got 2250w with 95w of drive, as measured with an Array Solutions Power Master. Tube is good and puts out full power. I have not had this amp on the air at all since the improvements. Price is $2400 with good tube, brand new PC boards and VHF suppression. Prior to MFJ closing the doors, new AL-1500's (without these upgrades) listed for $3900 at DX Engineering WITHOUT A TUBE. Roy -- AD5Q ________________________________________________ Brazos Valley Amateur Radio Club BVARC mailing list BVARC@bvarc.org http://mail.bvarc.org/mailman/listinfo/bvarc_bvarc.org Publicly available archives are available here: https://www.mail-archive.com/bvarc@bvarc.org/
