- 2023
- Dec
- 9
I have to fix the equipment before I fix the equipment.
Earlier this year, I went to the Cuyahoga Falls hamfest and brought home a Regency EC-175 frequency counter. This device has a OCXO in order to maintain a low PPM deviation for FCC compliance use. It’s really kind of an odd piece for Regency, and was going for next to nothing.
https://wereboar.com … yahoga-falls-hamfest
The Regency counter works, but is off by a considerable margin. I suspect this is probably just the 10MHz oven needing some adjustment.
My plan was to poke around inside of it and determine what was what, as I don’t have a service or operators manual. (I’ve since found an operators manual and will post it as soon as possible.) I was planning on using a cheap Lodestar signal generator and my Fluke 1910A 125MHz frequency counter to try and bring the Regency into adjustment.
So I set up, and…the Fluke counter doesn’t work. It will work as an up-counter, but won’t count frequency input. Hitting the “CHK” button, I get nothing:
This should be showing me the internal 10MHz clock. I play with various things and get nothing.
Time to open it up.
Nothing looks burnt. The section I need is underneath the RF cover, so off it comes. The parts in question, according to the schematic, are at the back of the unit near the metal backplate.
But before we get into those parts, a quick power supply check is in order. There are two voltages, +5 and -12.
+5 = 5.02
-12 = -11.80
The -12V is a TO-5 can device, and is pretty warm. I’m not sure if that’s supposed to be like that, but since -12 isn’t in the oscillator circuit, I’m going to ignore it for now. The logic supply of +5 is fine, however, so we’re good there.
The parts I’m going to be interested in here are :
U5
Q7 (under the heat-shrunk connector in the foreground)
Q8
Y1
I’m not really worried about U9 here because if I don’t have any 10MHz, I’m not goign to have any 1MHz. U9 is a divide by 10, so we’ll worry about that when and if 10MHz is available.
U5 pin 10 should be 10MHz. There’s nothing, so move back.
Q7 Base should be 10MHz. There’s nothing there, either.
I’m now going to switch the counter to EXT mode, as to remove those two parts from the circuit.
Q8 is an interesting part here. It’s a JFET, and the schematic appears to show a 2N3819. (It actually looks like SN3819, which isn’t a valid number.) However, that’s not what’s in the unit. I have a J310 VHF JFET which has a different pinout.
Always be careful, sometimes manuals you find online contain older or newer revisions of the device you’re using!
This confused me at first, because I was trying to test it like a 2N3819 and was getting a short on Gate to Drain, Pin 2 to 1. What I was actually reading was Drain to Source, which should be a somewhat low resistance. In this case, I had 37 ohms. That’s probably fine for a JFET, since Drain and Source are mostly the same slab of silicon. Without pulling this guy out and testing in an active tester, I assume it’s good.
No capacitors appear to be shorted. The few resistors in the circuit are fine for what they are, and are well within tolerance.
That just leaves the crystal. I don’t really have any way of testing it. I can try capacitance, but the resistors in the circuit will ruin that low pF measurement, so the only way is to pull it out.
The conclusion is the oscillator isn’t. The assumption here is the crystal is bad. Maybe cracked or internally damaged from time or handing? I don’t know - I’m going to try and obtain something similar to swap in and see if it works. There’s also a possibility I could find a cheap TXCO or OXCO to put in the area where Fluke would have mounted a TXCO, which should provide a better device.
That assumes the device is operational up front. These aren’t known for being reliable as they age, perhaps I’m just wasting my time with this. But I know where the problem lies, so there’s no harm in getting a few dollars in parts to try and make it work again.
- 2023
- Dec
- 3
An MMD1 8080 Trainer
This guy was given to me, well, probably in the late 90s because it was missing it’s 8224 clock chip. The person that gave it to me, since deceased, didn’t really want to go through the trouble of finding one so he asked if I’d like the device instead. Sure, why not.
I eventually found an 8224 on a device at a show, and put it in recently. I then realized that, unlike most other trainers, this one has no LED numeric displays! Well… the HALT LED will light and extinguish if I play with the keyboard, so I assume something is going on since it didn’t do that before. I thought about dumping the monitor ROM, but someone has already done that. I also need to investigate the power supply, it has a very loud hum and may need some modernization.
It’s nothing really special, just another one of many 8080 trainers that were available on the market. It will go beside my FOX Z80 trainer and my BellMAC 8 device for display. After it gets a little cleanup, of course, the thing was filthy when I got it and I have not done a thing with it.
The monitor ROM and some other information is presented here: http://www.decodesystems.com/mmd1.html
- 2023
- Dec
- 1
Random board shot: The Bell (Model?) Telephone Desk Speaker
My grandfather worked for the Bell System Long Lines division for his entire career, and I worked for one of Ma’s manufacturing locations just before it got spun off into the atrocity called Lucent Technologies, so Bell memorabilia is kind of an interesting thing to me. I remember all kinds of things in my grandparent’s home that you couldn’t necessarily get as a consumer - one of those being desk speakers on every phone in the place. And there were many many phones, apparently being wired without incurring the Bell System’s multi-device charges!
This desk speaker, while not one of his (all of those vanished…) it’s very similar. Not sure of the model here, it resembles a 107A but has an on/off switch along side the regular volume control.
The old Bell System logo resides here, being much more visually appealing than the later, minimal logo.
The inside, of course, is all Bell parts. Speakers and microphone were made by or for Bell, capacitors from the Hawthorne Works, and even the plastic case and metal parts were probably stamped out and molded by a Bell facility. It’s a simple line powered amp and mic, used in place of the handset.
My mother tells me stories of having her father (my grandfather) call in from where ever he was working at the time (he traveled the country doing line installs) and having the entire family gather around one of these speakers. When you worked for the phone company, making long-distance calls didn’t cost you anything from the job site, apparently!
The most interesting thing about this device, of course, is the PCB. Right there it is, the orange Textolite “T” indicating that the raw circuit board itself was made in Coshocton at the 2nd Street GE plant, just a stone’s throw from where my grandfather’s depot was based.
It amazes me how far, and how near products from this plant roamed. They’re in almost everything made in the USA up until the 80s. All of that, of course, is gone - something we’ll probably be sorry we did one day (soon!)
- 2023
- Dec
- 1
The Heathkit IM-1212 in operation. Kind of.
I decided to put the Heathkit IM-1212 meter in operation as a bus voltage monitor for my network rack. It’s currently on the 5V rail, but I’m working on a solution to get it on both the 5 and 12 volt rails.
5.2V is about right, considering it’s something like 5.11V at the distribution board.
The oscillator adjust, which should be 0.85, is already off. That’s about par for one of these.
- 2023
- Nov
- 30
I didn’t take it because it’s not enough money…
I have enough time in the industry to comfortably “sit back and reflect on things that have happened over the years,” and one of those things that came up in conversation recently was why I turned down some positions that I applied and worked towards getting.
It took me some time to come up with a reason for this, but I read a short article about the same thing and that described it very well. It helped me put into words what my reasons are - that all of the positions I’ve been offered and turned down were either lateral or downgrades, pay wise.
There are a number that were serious downgrades in pay that just got tossed by the wayside because the company had not been truthful about what was being offered at the start. These places generally had a bad company attitude as well, and it’s probably for the best that they revealed their hand before I took the offer.
There are two that really stick out in my mind, however. One was a company looking for an engineering technician. This person would be entering a “Now apply what you learned” situation. The company offering this knew what I made currently, and knew I would be picking up and moving. I had a good feeling about this one, and assumed that because of the increased skill level required it would be paying accordingly.
“Accordingly” was a number based on some people I knew doing similar work at comparable companies.
They didn’t offer that number, and offered somewhat (not a lot) less than I told them I made currently. I turned it down. I received a call later from the company asking what they could do to make me interested. It’s the money, make me a reasonable offer for an engineering technician. You’re not giving me any reason to be attracted. I know the job is longer hours and more intellectual work, pay for that.
I never received any further contact, so I have to assume that they either went with their second choice or started interviewing again to find someone that would take their offer. I found their HR person on LinkedIn years later and extended a “Can I talk about that?” but never received a contact.
The second was more of a plain lateral move. The company did offer slightly more than I was making at the time (about $0.24 / hr more) but their benefits structure would have eaten up considerably more than that. It would have turned out to be a net negative with a longer drive. Again, the contact asked why I was turning it down.
It’s the money. It may be a bit more gross, but the net is less and you’ve not given me any reason to be attracted to your company - make me a better offer. You know what I said I’d like to see. I’m not leaving this job for that job when I’m not gaining any benefit. You seemed very pleased that I could pass your test and talk shop with you. You want my skills, how about a bit of compensation for them?
That didn’t go anywhere either. I did contact them later when some stuff happened, but they weren’t interested in talking anymore. No big deal there, I understand.
The takeaway here is I’ve had plenty of offers over the years, but in almost all cases it was the exact same thing I had or less, even if the position was a step or two up. At no time did I feel the company recruiting me understood that I wasn’t going to leave something for something identical, that I wasn’t going to take less. They just knew I wasn’t taking their offer but were unwilling to offer more.
It’s all kind of frustrating, but I’ve since read other’s accounts of the same thing. Someone wants them, but offers essentially the same thing they have and wonders why they don’t come running. We’re not in this for our health, it’s the money. If you want a special skill or years of experience, offer the holder something that attracts them.
If you don’t - you don’t get it. That’s all there is to it.
I’ve talked in depth about some of those experiences. If you’d like to read them, you can find them here: https://wereboar.com/stories/
- 2023
- Nov
- 29
An odd thing with Flatpress…
This blog runs on a self-hosted system called Flatpress. It’s what it sounds like, it’s a Flat file publishing system. No databases or anything, just a bunch of files.
One of the odd things I’ve noticed about this system is how it pulls thumbnails and presents them to the user. Sometimes the thumbnails will be blurry, and sometimes they won’t. No idea why, save it seems to be related to the name length of the folder the images are in - and perhaps the name of the folder?
Thumbnails in this case refers to both the reduced size (but still large) images on a normal page using the img tag, as well as those presented by the gallery plugin I use.
For example, a recent post about the Fort Wayne hamfest gave me blurry images for the thumbnails. While they aren’t necessarily clear, you can generally tell what they are - not so this time. I changed the name of the folder from “fh23” to “fortwayneh23,” pointed the page to the new folder, and the thumbnails look good.
Later me wants to add some things - Don’t start your image or folder names off with a number, always use a letter. I don’t know why, but using a number will result in a blurry thumbnail. If you get this, change your names and delete the thumbnail folder in the image directory where you have your files stored!
I have other folders in my image directory that are only four letters long, so I’m really kind of clueless here unless it’s some random thing with both length and name. If you’ve run across that yourself (and it doesn’t matter if I’m using the gallery or normal view) then try to rename the folder your post’s images are in to something longer than 4 characters. It may resolve your issue.
- 2023
- Nov
- 29
Pictures from the November 2023 Scott Antique Market
This show takes place monthly at the Ohio Expo Center (State Fairgrounds) and runs from November to April. There’s generally not a lot of electrical goods here, but this time I was surprised. A lot of radios and other technology related goodies showed up. I suspect this is in part due to the show being the first one of the season, and being close to the holidays - everyone is looking for that perfect gift.
While not all of the pictures I took were of electrical things, I found the stuff to be interesting (or strange!) enough to take a picture of. I’ll probably hit next month’s show as well, so stay tuned!
- 2023
- Nov
- 29
Pictures from the Fort Wayne Hamfest 2023
This year’s show seemed to be a bit smaller than normal, but it may have been just my imagination. Regardless, there was a lot to see and the show was, as usual, busy. I tried to limit what I brought home to things that were on my want list, and I mostly did so - only diverging for a book that looked interesting. I’ve written about one of the pieces, a meter from Heathkit, so check out the posts just previous to this one for a look at that piece.
- 2023
- Nov
- 27
November 2023’s Scott Antique Market
I was quite surprised, there were a lot of electrical and other related technology items for sale at the show. While none of them really wanted to go home with me, they were fun to look at and talk about with the vendors. I’ll probably head out there for the December show as well, perhaps the holiday shopping season will bring the really odd stuff out of the woodwork.
I’m currently processing the pictures from the show, so stay tuned!
- 2023
- Nov
- 26
A Heathkit IM-1212 from the Fort Wayne Hamfest - making it work again.
One of the things I picked up at the Fort Wayne hamfest was a Heathkit IM-1212 NIXIE DVM. This device was sold as a kit, and was also known as the Bell & Howell IMD 202-2, as well as a DeVry branded unit. They were all the same, with different branding on the front panel.
The device itself is a 2 1/2 digit meter, and uses discrete components - all ICs are common TTL stuff - to do it’s work. It’s not the most accurate thing in the world, but I imagine it was designed to help you learn about A/D conversion and other concepts while giving you a device that you could (mostly) use at the end.
This unit was sold as working, which I verified with a 120VAC inverter/battery pack from the tool company in the harbor. I offered the guy a $20 for it, which he accepted and I took my purchase home.
It’s not in bad shape for the age, a bit of discoloration on the front panel and the obligatory tape residue on the top of the device.
It came with the original instruction manual, which is useful for troubleshooting any issues.
All of the tubes are nice and bright like it doesn’t have many hours on it. Even the NE-211 bulbs that are normally shot don’t exhibit any flickering or problems ionizing.
I did notice a few issues, there’s a rattle inside. Something is broken. The negative jack is also loose, which is probably just a nut come loose. The device also doesn’t respond to any input - something to do with the loose negative jack, perhaps?
Time to open the top cover. Notice the line of big beige resistors on the left and the one blue specimen at the bottom? These are calibration resistors, and one had apparently broken at some point, as the rattle was the remains of an old part. The original owner hadn’t removed the debris for some reason.
You’ll also notice there’s a number written on the paper cover. This is the DC calibration voltage as provided by Heath. It’s wrong, so ignore it and get a good 3 2/3 digit meter and measure the DC cal point. Mine turned out to be 1.901, so I used that later during calibration.
I discarded the broken pieces and looked at the negative jack. Sure enough, the nut was backed off, and that was because the cheap plastic threads on the jack were worn. While it tightened up, one more turn would knock it back. That will have to be replaced if I want to put this into service, but I think where it’s going it will be connected and let set as a monitor device.
The loose jack was also the cause of the no reading issue. The loose jack and solid wire insured the wire itself broke. That was an easy fix, just a quick re-solder and we’re back in business.
Time to hook it up to a power supply and see what it reads. It’s close, I guess for something of unknown quality it’s fine. As I stated earlier, these weren’t known for being the most accurate of devices, nor were they known for staying where you put them. Fortunately, the DC calibration is pretty easy, just requiring the device having been on for some time to temperature stabilize.
I’ve already posted the DC calibration procedure for someone, so if you haven’t read it you can do so here: https://wereboar.com … t-im-1212-nixie-dvm/
I don’t think there’s much more to say about this device that hasn’t been said already by many others. I’m planning on making a small board that switches between the different voltages in my network rack, so that may show up at some point. Until then, stay tuned for pictures from Fort Wayne and the Scott Antique Market at the Ohio Expo.