I went back several months and also looked at the power cube and sgc-2000 groups. Unless something is burried under another topic, I didn't see anything related to current production.

What's the story with this amp? Last I heard they were re-designing the amp with new sourced finals and were soon to release it. That was three years ago. Any news or rumors?

The ISA bus connections do not include the B20/4.77 clock or use B30/14 mhz.  The UART has an independently derived clock source from an onboard rock and last I checked I recall it's presence at the clock pin. The bus glue chips between the UART and the ISA bus are a 74hct245 bus transceiver, 2  74HCT138's as 3/8 line decoders, a 7400 and 74125 both HCT as well. Presently, the only slow ISA bus machine that I have alive is a 75 mhz Packard Hell that I use for RSS and GPIB control in my shop. I have an old ISA HP/GPIB card running happily, so there's no problem with the bus. The PCB-88 is otherwise undocumented beyond two schematics. Unlike the PK-88 and PK-232 that had hardware manuals available. The PK-88 is near identical I understand except of course for the bus interface section in question and has a serial interface instead. Randy at Timewave seemed to have no knowledge of the board, no supplemental docs available, and did no repairs. He could only could sell me a new battery several years ago.

I took a look at the board and it despite the schematic showing a 8250, the board has a
socketed 16450 UART. I'm going to try the 16550.

Thanks for the links. The TAPR posting confirms my original suspicions. I've never known anyone to have owned one of these boards. While I ran into a lot of DOS software that increasingly would not run or run properly, the supplied Packterm and XPware software would work with the pk-232, so I never doubted it was the host software. The board would be identified as an unknown modem and physically held the port and irq the board was set to, but using generic terminal software such as Procomm wouldn't register any response either. I've sort of suspected the 8250 UART as it was a problem with earlier serial cards and modems on faster AT compatibles. Later cards used the 16450 and 16550 UARTS. I wonder if anyone ever investigated that. The link for the backplane project was interesting and is actually why I'm holding on to the board. I've been given a backplane with a 386i processor card and embedded DOS along with a serial/parallel combo card that was used in a marine communications terminal that might be a future project.

I've held on to this ISA packet board for years, even replaced the battery a few years ago. I have a nagging question that Timewave appears not to be able to answer at the time I enquired about it around 2005 when I upgraded my two pk-232s. The board was perfectly operational on a '286 machine for a couple of years. Upgrading to a '486 during the 90's, the board apparently wouldn't communicate with any software. Same with a Pentium 90 and subsequent 300 and 500 mhz boards that still had ISA slots.

I've always wondered if the bus speeds of the later computers were the reason the board couldn't be initalized and it required the slower speeds of the old machines. DOS Utilities such as Whoa or Moslo didn't make a difference or the old AT command of ctrl+-

I'm just wondering if this was a bus speed issue or if there was a failure between the transition between the 286 and 486 upgrades. Besides Pkterm that AEA suppled for DOS, I couldn't access the board using the old Aries or Gary's later WinXP DOS or Windows versions.


Anyone know if these boards are dependent on old XT/AT ISA bus speeds? 

There isn't an entry for these supplies in the reviews. They seem to be going for inexpensive prices used. I read some threads on a another website that said these supplies are the same as the Samlex 1223 minus the fan. I'm curious outside the conservative specs if these supplies are capable of 15A ICS/20% duty cycle for a 40W radio @ 15A. Anyone know the capabilities of these supplies?

Those of you that get the latest flyer and the store versions as well every other week will appreciate this. Some very good deals and great coupons, but I really like the multitester featured in the advertisement. Free aluminum flashlight coupon too.

http://www.brownebagracing.com/pictures/hf_tool_sale.pdf

I looked at some of these starters and most were much too heavy in the switch pull and the stiff cord. Foot pedals seem like a good idea until you used them for any amount of time, ditto inline switches. I finally found a good substitute of all places in a hospital. The patient call buttons used to signal assistance are very heavily made and booted switches. Most all have standard 1/4" mono, right angled phone jacks with tinseled cords that plug into the intercoms. You can find these on E-bay either as surplus or new stock. They comfortably are molded in some material like rubber to fit in a closed hand for extendend periods of time. 

If the OP does a lot of homebrewing, this is a strange question to ask unless one enjoys using 110V $10 firestarter soldering irons. Maybe a nice homebrew project might be a light dimmer and neon bulb pilot light inside an enclosure with a controlled output outlet for the iron. That may sound like a joke, but it was essentially what my Pace soldering/desoldering station that I bought 30 years ago was complete with two Leviton wall dimmers inside.

For everything except SMD work, classic WTCPN/S type "magnestat' type irons have been the professional standard. Sixty watts is enough for most all jobs and you'll only buy one or two in your life if they're still made they way they used to be. Good sized grip that's not fatiguing or hot after hours of work.

For SMD work, you'd be better off with a Hakko 936 or clone station with it's smaller, pen sized iron. You usually get what you pay for, but in my experience some of the clones are just as good as the real deal. The 936 has become the defacto service standard that you can buy aftermarket tips for every need, heaters, replacement irons very inexpensively nearly everywhere.

You get what you pay for Clint. I wouldn't get my hopes up too high. We have two of these in the vehicles and one of the packs with a combined AC inverter sitting in the house for an emergency. They're essentially pitch and toss after the battery dies. We used to have 3 of the larger, 650A/1200 peak versions that were identical except for the big bump on the back to accommodate the larger gel cell that lasted about 2-3 years. Once the battery dies, it's not worth the cost to replace. The batteries cost more then we paid for the first power packs and shipping. There's really no charge circuit to speak of, just a trickle charge from a small transformer that can take days or a faster charge from your vehicle's cig. lighter.....er we don't say that anymore...aux power jack. The meter is a cheap iron vane type that shows the battery voltage when the button is pressed. The LED only shows that the unit is charging and is not a charge complete indicator. The case is a sort of flimsy blowmold with little room for anything else. That's all besides the flashlight which can be very handy fumbling under your hood during the dark or emergency light source. Good for what it is. Outside of making up a power pole pigtail or dedicated cable to a radio from the jack, it's not worth the effort. Even if you were to bolt on a small, cheap inverter, one of the packs that has one built in would still be far cheaper. Poke around to see if you can find a 20% off or other discount coupon code before you buy.

Those of you that do board level repair, how invested are you in equipment and do you have a limit to the rework level that you're willing to do?

 

I use a 30 y/o+ Wolfe (Kyowa Optical) inspection scope with a boom if I need it, but it takes up a lot of room and a royal pain to work with. Most of my work is done with a bench mount magnifying ring light or an inexensive magnifying headset with inserts.  My wife uses a set of binocular eye glasses made by Craftoptics that seems to work a lot better then a headset or the scope. They're a bit pricy, but there are other companies that make similar ones for less. Madeltech has several available specifically for SMT work for about 1/3 of what my wife's cost.

http://craftoptics.com/

http://www.madelltech.com/loupes.html

Only in the last two to three weeks or so has there been stock available and the website updated with higher prices. Prior to that all products showed out of stock. I tried e-mailing them and only got an auto confirmation, but no reply. There was no business address listed last time I checked the website and application notes. They appear to have some very nice and well made products with a lot of thought and effort invested in the applications notes. There are no supporting reviews or mentions on this website, QRZ, or any other sources I could find on the net that anyone had actually done business with them. There were no independent references I could find besides domain registration. The Stenbock Communications production company that they're a division of and linked by the website is equally nebulous. They offer flight training videos with testimonials, but there's no videos on the website offered and little else like the PreciseRF in terms of offering an address or phone number or any other signs of an operating business as of this writing. It's either a placeholder or they still haven't finished developing the website.

I'm sure they're a legitimate business and just getting started. However, there's too many red flags at this point for me to have placed an order in my opinion. The least they could have done was to write me back. It's really a shame and their loss. I ended up ordering a return loss bridge and an in-line sampler from other sources. I ended up paying a lot more then what their products cost and theirs would have been more then sufficient. I wish them well in their venture.

I would tend to disagree for most ham usage to get an elaborate, triggered lab scope. Years ago when I got licensed, the dictum used to be that a scope for station use was good enough if it "got a green line". Times have changed though with elaborate synthesizers and microprocessor control in amateur rigs. For years, the Eico recurrent sweep scope I owned was enough for my bench qualitative work. I.E. the vfo or heterodyne oscillators were functional, you could trace drive, AF or IF signals. So what if you exceeded the -3db points of the vertical amp, you still could see the presence of RF at higher frequencies, just attenuated. Most point measurements were made with a vtvm or rf probe anyways if you needed an absolute number to compare with service manual notations . If you needed the bandwidth to see the output, you went directly to the plates of the crt which were often good beyond 30mc with a line sampler....same idea with a station monitor scope. The OP mentions that he's primarily interested in tube and vintage equipment. An old recurrent sweep TV scope would be sufficient. Unfortunately 40+ years later, many of these tube based scopes have seen better days and would probably be full of leaky paper caps and drifted resistors. For the money, a rebuild wouldn't be worth it and near the price of a more recent higher bandwidth triggered scope. There should be a number of "Station Monitor" scopes of the 70's that were solid state except for the CRT that also had general purpose vertical and horizontal inputs as well as a tuned IF input for their companion receiver and some sort of line sampler/attenuator. I did a lot of repairs on the spot with first my Heathkit SB 610 monitor scope and latter Yaesu YO-901 using the direct vertical inputs with a probe without having to drag the rig to my garage shop. It's nice to have a good lab scope if you need it, but you'd do better in learning to service your station with a simpler scope. If you could find one, Leader used to make a solid state version of their LB-310 specially set up for ham use with a coaxial sampler that would make a great first scope that would also lend itself as a good general purpose scope. Many of the service and educational vendors had some very useable 20mhz private label  triggered sweep scopes that were simplified for service or student use that would make great starter scopes for the money. A great project would be making your own coaxial line sampler to use with one of these.