I probably wasn't clear; I didn't repair the Nikkor - it's still fine. I meant I'd repaired another lens with oil on the blades (a Miranda 50mm).
It can be a bit intimidating, but ifixit have a ton of useful instructional videos and also sell some useful spares and toolkits.
Is there a thread , what did you last break? My hats off to anybody successfully repairing old junk.
USB PC oscilloscope I designed myself.
I built on up and just noise on the pc screen.
So re-soldered A2D and that fixed it.
Just applying solder with syringe then heating doesnt always work.
Afterwards, I add plenty of flux then drag solder using iron.
I suspect the A2D's have been stood a while and pins are a little tarnished.
I built on up and just noise on the pc screen.
So re-soldered A2D and that fixed it.
Just applying solder with syringe then heating doesnt always work.
Afterwards, I add plenty of flux then drag solder using iron.
I suspect the A2D's have been stood a while and pins are a little tarnished.
I hate repairing old stuff or stuff someone tried to fix and messed up.
Old stuff tends to have dodgy pots and jack sockets.
Ripped tracks can be a nightmare to fix.
Old stuff can have rat pee, and other deposits.
Also leaked electrolytic caps, and you are mostly doing it as a favour.
Unless it is a family heirloom or belongs to somebody who will not pay, it is not worth it.
Oh, and add disintegrating plastic to the list...and odd voltage power supplies, which are hard to replace.
Also leaked electrolytic caps, and you are mostly doing it as a favour.
Unless it is a family heirloom or belongs to somebody who will not pay, it is not worth it.
Oh, and add disintegrating plastic to the list...and odd voltage power supplies, which are hard to replace.
Once it leaves the realm of "it'd be fun to try and see if I can get it to work"... The Heathkit O-Scope I picked up this summer at a yard sale fell squarely outside of that. It's now a pile of parts, with a dangerous fully exposed CRT tube I have to deal with...
I'm afraid to touch anything these days because I'm in the period of a BAD KARMA. Older I get more superstitious I become 🙂
Besides , there are only a handful of vintage pieces worthy of attention.
Besides , there are only a handful of vintage pieces worthy of attention.
Last weekend my son and I replaced the rear wheel bearings on his Toyota Landcruiser Prado preparing it for his Nullarbor trip of around 7,000km at Christmas. What a job! Removing and replacing the bearings from the axle halfshafts involved using a 100 ton hydraulic press and much swearing trying to make steel plates to fit under the bearing flanges to press against. Then the inner race remained on the axle and required welding a bead around them with a MIG welder to heat for removal. One worked, and one didn't because of heat transfer to the shaft (we took too long), so it was then out with a air die grinder, cold chisel and a big hammer.
Then replacing the handbrake shoes, a job you'd expect to be quite easy, took hours because of lack of access and poor design - and I could still not get it. Afterwards, I found no-one on the net with any reliable easy way, and read that some people just give up and go without a handbrake. One guy took 11 hours to replace the shoes!
But we did it...after picking up a series of tips online and having a long think, the first side took an hour; the second, 30mins. But it took extreme patience!
Then replacing the handbrake shoes, a job you'd expect to be quite easy, took hours because of lack of access and poor design - and I could still not get it. Afterwards, I found no-one on the net with any reliable easy way, and read that some people just give up and go without a handbrake. One guy took 11 hours to replace the shoes!
But we did it...after picking up a series of tips online and having a long think, the first side took an hour; the second, 30mins. But it took extreme patience!
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A couple of years ago, the Sony TAN-15F amplifier. Bought extra cheap as defective. One channel had a high DC voltage at the output, the other was OK. I repaired it first to hear if it was worth going further. The repair was not difficult, it was just bad solder joints. After listening, a general overhaul and modification was arranged. I replaced all electrolytic capacitors, resistors, speaker connectors and wired with VDH CS18. I bypassed the A/B switches, heavy nonsense that is. Also added an IEC connector and a safety GND. Very good quality little amplifier, for my sister and brother-in-law.
Attachments
Use a CO2, Nitrogen or Argon bottle, it freezes the area, and shrinks the metal just enough to pull out easily.
Read up about it.
Observe precautions, it is a bit dangerous to have skin contact with metal at such a low temperature.
Easier than welding / chisel / hammer etc.
Read up about it.
Observe precautions, it is a bit dangerous to have skin contact with metal at such a low temperature.
Easier than welding / chisel / hammer etc.
A cross threaded bolt stripped the thread out of the m4 hole I bolt the bike bag rack to. 5mm aluminium.
Been a long time since I cut a thread (school50+ years ago) so had some nerves, but drilled the hole out to 5mm and tapped it for m6. Perfect.
Been a long time since I cut a thread (school50+ years ago) so had some nerves, but drilled the hole out to 5mm and tapped it for m6. Perfect.
What I didn't repair 🙁
For the third time in less than two years my Pure DRX 701ES DAB tuner suffered yet another failure. This one is bad news, the small toroidal is kaput.
Wondered exactly what had happened, was listening to a CD and suddenly after hearing some relays drop out all was quiet. The amp was still powered but all my source components were 'dead'. These are all fed from a little wall mounted box behind the amp that has a single mains input and three relay switched mains outputs. The on/off command is via an optical feed from the amp.
Turns out the tuners transformer has some weird short internally. It not only blew the 100ma fuse of the tuner but also took out a 1.6 amp fuse in my little relay box.
The transformer primary reads around 180k (I know) and yet instantly pops a fuse with secondary unplugged. Lots of these tuners from the usual suspects with quite a few described as 'will not turn on'. Most faults are caps and diodes and regs. Given this is only DAB and many stations are now DAB+ I'm going to replace it with a new Rotel DAB/FM/Streamer, the Rotel T14.
For the third time in less than two years my Pure DRX 701ES DAB tuner suffered yet another failure. This one is bad news, the small toroidal is kaput.
Wondered exactly what had happened, was listening to a CD and suddenly after hearing some relays drop out all was quiet. The amp was still powered but all my source components were 'dead'. These are all fed from a little wall mounted box behind the amp that has a single mains input and three relay switched mains outputs. The on/off command is via an optical feed from the amp.
Turns out the tuners transformer has some weird short internally. It not only blew the 100ma fuse of the tuner but also took out a 1.6 amp fuse in my little relay box.
The transformer primary reads around 180k (I know) and yet instantly pops a fuse with secondary unplugged. Lots of these tuners from the usual suspects with quite a few described as 'will not turn on'. Most faults are caps and diodes and regs. Given this is only DAB and many stations are now DAB+ I'm going to replace it with a new Rotel DAB/FM/Streamer, the Rotel T14.
Oh great! DAB+!
Now my DAB radio is nearing obsolescence.
At least it also receives FM and no sign of that being turned off anytime soon in the UK.
Now my DAB radio is nearing obsolescence.
At least it also receives FM and no sign of that being turned off anytime soon in the UK.
Classic FM (on DAB) is moving to DAB+ in January I believe.
I remember when DAB was introduced back in the mid 1990's and not all that long after there was talk of FM being turned off by around 2005 and yet here we still are. Then the rumours of DAB+ started and it all caused so much uncertainty that hardly any manufacturers carried on designing and bringing out decent DAB tuners.
I remember when DAB was introduced back in the mid 1990's and not all that long after there was talk of FM being turned off by around 2005 and yet here we still are. Then the rumours of DAB+ started and it all caused so much uncertainty that hardly any manufacturers carried on designing and bringing out decent DAB tuners.
Bought a pair of KEF "eggs" at the local thrift. They had stands and cables so I was able to easily "click test" them in the store. Alas, ultimately one exhibited the classic "skritch-skritch" of a blown speaker, when the woofer cone moved.
I disassembled it and the magnet assembly - containing the tweeter - simply fell off the basket as I removed it from the enclosure. Easy fix I thought, however any position I replaced it in, rotating it, still had the rubbing noise. The VC appeared intact, round, no blistering on the kapton former though some evidence of moderate heating in the center of the winding was seen.
I let it sit for a while. Coming back to it, I noticed a strange "seal" of very thin butyl rubber between the tweeter post an woofer VC. Upon closer examination, there seemed to be an annular tear around that post. Unsure how it worked when intact, I merely removed the section from the post and put the magnet assembly back on the basket. No more "skritch-skritch"!
A little rubbery cement atop the old adhesive and, after cure and reassembly of the speaker into the "egg" enclosure, bolt back on the stand and I have my stereo pair again. Nice for close, headset like monitoring of my playing and vocals through my M-Audio NRV-10 mixer, which I enjoyed up until that "skritch-skritch" distortion in one really started bugging me.
Now, I wonder what the condition of the other speaker is and why it hasnt yet suffered the same fate? Magnet about to fall off too? Ah, adhesives that dont last for 20 years...
I disassembled it and the magnet assembly - containing the tweeter - simply fell off the basket as I removed it from the enclosure. Easy fix I thought, however any position I replaced it in, rotating it, still had the rubbing noise. The VC appeared intact, round, no blistering on the kapton former though some evidence of moderate heating in the center of the winding was seen.
I let it sit for a while. Coming back to it, I noticed a strange "seal" of very thin butyl rubber between the tweeter post an woofer VC. Upon closer examination, there seemed to be an annular tear around that post. Unsure how it worked when intact, I merely removed the section from the post and put the magnet assembly back on the basket. No more "skritch-skritch"!
A little rubbery cement atop the old adhesive and, after cure and reassembly of the speaker into the "egg" enclosure, bolt back on the stand and I have my stereo pair again. Nice for close, headset like monitoring of my playing and vocals through my M-Audio NRV-10 mixer, which I enjoyed up until that "skritch-skritch" distortion in one really started bugging me.
Now, I wonder what the condition of the other speaker is and why it hasnt yet suffered the same fate? Magnet about to fall off too? Ah, adhesives that dont last for 20 years...
Glad I didn't buy a houseful of DAB tuners then!
BBC state Channel Island services are on DAB+ but no mention of how long DAB will last or if stations might move to DAB+ in the future.
Until your post I was in blissful ignorance.
Ofcom have an interesting report that states half of radios sold (in 2023) are analogue only and not all current DAB radios being sold are DAB+.
https://www.ofcom.org.uk/__data/assets/pdf_file/0033/268809/DAB-radio-report-2023.pdf
Interesting report, I'll have a read at that one later. Similar happened with Freeview, there are some channels on there (not just the normal HD stuff) that older equipment can not receive.
https://ukfree.tv/article/1107052554/Rebuilding_Freeview_High_Definition_from_2019_onwa
https://ukfree.tv/article/1107052554/Rebuilding_Freeview_High_Definition_from_2019_onwa
Ha ha ha! I don't need to read about it, I am well familiar with freezing and heating methods. I've noticed you post here like you're an expert on just about everything. Have you ever done this yourself? The axle has significantly more mass than the part to be removed, so you can't readily achieve the temperature differential required. Not only that, but a steel shaft doesn't shrink from cold to the extent a collar or bearing race expands from heating. In some instances, once the bead of weld is completed, the race drops off the shaft without being touched.
We were working in my son's machine workshop that repairs megabuck machines for the mining industry. $500k gearboxes and $60k hydraulic pumps are the norm. Removing interference fitted bearings is a daily event, some done in the field on a broken machine down a big hole that can't move until it's fixed, and costing big bucks every hour it's out of action. The main issue with the Prado was access to the bearing flanges for pressing.