212+j212 is a Zmag of 300, but that doesn't equate to a 6:1 VSWR with a Z0 of 50 ohms; it's 8.6:1 VSWR. I think the previous poster was trying to compare two different complex Z's that both yielded
I'm looking for RF device databooks from Thomson, SGS-Thomson, ST Microelectronics, or any of their other incarnations. I'm particularly looking for older (1980's/1990's) databooks that includes the
High-temp as in 200 deg C? That's what most polyamide magnet wires like Thermaleze are rated for. Enamel-coated is rated lower, like anywhere from 120C to 200C depending on the type. I've bought mag
W6PQL has an LED bargraph board. His design uses a tapped string of diodes and their associated forward drops for segmentation. You could also use the venerable LM3914. -- Jeff WN3A -- This email ha
Two separate CW transmitters combined with high isolation between the two, or two separate signal sources combined into an external low-IMD (typically class A) amplifier used as a driver. The former
I have some questions on these amplifiers regarding their history and changes made to them over the years. I know they were originally made by Command, and then sold to Palstar, and then back to Comm
The slug contacts are silver-plated, but can still result in intermittent contact if not "wiped" by a rotating slug now and then. If it's been sitting a long time, they may just need some TLC with a
A friend's 87A showed up on my bench. The symptom is fault code 1 (receive PIN back bias voltage not at minimum required level with key down and no RF drive) as soon as the key line is closed. This 8
I'm the OP on the topic of the 87A troubleshooting. Just a couple of comments: To be clear, the PIN diodes that I was discussing are in the receive RF path. They are reverse-biased to 700+ volts when
Unless it's been modified, an 87A shouldn't have a neutral, just two legs and ground. What kind of plug and receptacle are you using? Are they 4-pole (L1, L2, N, G), or 3-pole? If the latter, unless
The main bonding jumper is installed at the service disconnect. It is not "perferrably" done there, it is required that it be done there, and only there. In residential services, it is fairly common
Agree with everything you said Jim, with one exception: Not quite right. In those few exceptions, you are permitted to bond the NEUTRAL to the frame. You are not permitted to use an EGC as a current-
Start with something non-abrasive like a piece of cardstock. First run it through dry, then take another clean piece of the same with a drop of IPA or contact cleaner on it. If that doesn't do the j
I'd be suspect. The X500HNA ("heavy duty") is only rated for 200 watts. I've never pulled the guts out of an X500HNA and an X510 and laid them down side by side so I can't comment on why one is rate
Yes, and it seems that limit was adhered to by amateur amplifier manufacturers about as well as speed limits are obeyed here in the US :-) As others have said, I think Steve would find a significant
I didn't know Alpha had released their source code or firmware images to the public domain - have they??? -- Jeff WN3A -- This email has been checked for viruses by Avast antivirus software. www.ava
I'm probably going to catch hell from a moderator, but virtually everything that is written below is so wrong that it's not worth picking apart. But to possibly prevent someone from doing something t
I'll go one step further and comment that the differences vary at a more granular level than just country to country. Here in the US, electrical codes are adopted by the AHJ (agency having jurisdict
L14-20 is the smallest they go, no 15A in a 4-wire 125/250 twistlock. about the still If skinny is what you're after and you can't find regular SJ and it's going to be used only indoors, maybe look
I went to place an order for Sage Labs (later API, now Spectrum Control) "Wireline" twisted-wire cable often used for quadrature hybrids only to learn that API has discontinued the product line. It h