You deserve a medal for taking that on. I would have called it a basket case and chucked it in the bin and told my friend it got lost in the post 😜. You never cease to amaze me as to what you are prepared to take on.
Well, originally I just wanted to do some cleanup and fix that busted corner... but it snowballed from there, and it does make for an interesting video project.
Hi! . . .It amazes me just how these sets were put together in the factory in the first place, especially the inaccessible wave change switch mechanism! . . .I had a Telefunken "Magnetophon 55" to repair for a Vintage Radio Forum Member, and I traced intermittent loss of playback volume to a defective R/P switch contact in the grid circuit of the EL95 replay output valve, but seeing the forest of wiring and components attached to this switch assembly, desoldering and removing them all to fit the spare switch contact assembly I had simply wasn't on, so I bypassed it with a 0.1 μ capacitor to maintain the signal path on replay, then if I see the unit again, I can let the owner know in the future that the whole R/P switch contact assembly may need replacing which is a big job!
You know your radio is old when 3 out of the 4 knobs and the entire pre-printed list of radio stations have nothing but static on their spectrum anymore, and the 4th is pretty much digital by now. :D A beautiful project.
There wasn't really much between anyway: it scraped off pretty clean, except the few spots where I accidentally scraped the wood and had to apply the putty.
WOW! . . .I thought you might have got the OpenScad out to design and print a new front bezel in 3D for it! . . .How do you work out where all the components go? - do you have an Original Loewe-Opta Factory Manual to work from? . . .Another thought has occurred to me - when you do a full restoration on an old set like this with many components having to be dismantled, cleaned and serviced and/or replaced, wouldn't you have to completely re-align the circuits with a.m. and f.m. radio Signal Generators afterwards? Chris Williams
The schematic for the model is out there, yes. The "remake a new bezel" option was my second option, but that putty stuff holds up surprisingly well. The alignment is on my to do list, yes. I doubt it will be far off from nominal though, as all the frequency critical capacitors are ceramic ones, and those are still good. Also the coils won't drift at all. But some of the tuning lugs are stuck in the coils, and to get them out without damage is my current hurdle.
2:00 This speaker plug also fits into the mains socket. 4mm connector 19mm spacing. Never mix these up, the speaker only has a few ohms and will certainly be destroyed by AC 230V. This happened to a friend of mine.
Yeah, these old banana style plugs sure fit the power sockets nicely. I'm using some of my test leads from my insulation transformer outlet quite regularly. Sadly, more modern devices come with these stupid sleeves over the plug, so the new wires won't fit the old plugs...
The nicotine coating on the components is quite mild. Used to hate working on TV's from heivey smokers households. Everything coated in a horrible thick tar, ash and dust mix. There were a couple of occasions where I did refuse to work on them because they were so bad. Smoking and open fireplaces are not friendly to domestic appliances.
I've begun studying the isolator board. I intend to check the passives. Did you follow the ack signal paths to find the bad inverter? Did you use extender boards to access the pcb?
I don't have an extender PCB; but for troubleshooting, I left all the shielding off and had the left side panel removed too, that gave me a bit of access to the test points and quite a few components. As for the inverter: it wasn't related to the ACK signal, that one worked on my side, just pointing out that these TTL chips can go bad in general. But what you could do to find out which board is at fault: Remove all PCBs except the controller and isolator. Hook up the "ACK" line on a scope; I'd use the controller input for that, seems to be the best accessible. Then, one by one, add the cards and power on. During power on, the controller talks to all of the cards, one by one and expects an ACK signal, so you should see one from the current card. The only exception AFAIK are the oscillator and the high voltage ones, but those should also not give the Err6 on startup for that reason. They only say Err6 when requested by an output. That way, at least you know which card isn't doing the power on reply.
I'm not sure which bella you have, there are multiple models, but looking at schematics, the chassis are not floating, i can also see stuff grounded to the chassis in the video.
Ah! It's a 4705W - and with "floating" I meant "with respect to mains input", sorry if that wasn't worded proper. The chassis is certainly the ground of the whole thing, just not "mains earth". The original didn't have a grounding wire to begin with. There's just a capacitor connecting one side of the input to the chassis, which I replaced with a "Y" class capacitor by now. But the mains earth should normally not be connected to the chassis. I think that might interfer with some antenna setups which are grounded at the antenna side, but that's just a hunch...
@@atkelar unless I am mistaken floating would be when you have a transformerless radio where the neutral or worse the hot wire is not connected to the chassis at all, but has its own bus write often called B-. This set has a mains transformer, bridge rectifier and antenna ground lug all connect to ground directly. Every voltage in it is with respect to the ground so it's not floating. In olden days people would connect antenna ground to a pipe from a radiator or something. But that's messy. And who has an antenna these days? The ground in the mains cable makes the chassis a little safer and it provides a ground for the antenna if your electricity installation is correct. I have grounded every radio with a mains transformer I ever worked on. But don't take some comments word for it, ask on tube radio forums. You should get more or less the same answer. Some purist don't connect the ground wire because it's not original, but those are people with antennas on the roof and a ground pin for the antenna. If you're worried it affects performance somehow, just run it with and without the earth wire connected. I'll repeat my earlier warning that this goes out the window for sets without a mains transformer.
Oh, I'm pretty sure the transformerless versions are called "hot chassis" because they are directly connected to one pin of the outlet. Ideally neutral, but with non polarized plugs it could be either. "floating" has been used in all contexts I've seen to indicate that there's no set voltage (electrical potential) assosicated with it, at least from a given perspective. So from the mains outlet perspective, the chassis is "floating" and you shouldn't be able to measure any voltage between the outlet and the chassis. From the perspective of the secondary side, it's of course connected as the ground line (and in this case also one line of the heater string) To me, the question whether or not to ground the chassis is mostly: What plug do I want? If I put in a three-wire connection, I naturally also ground the chassis for good measure. But since I was provided with a two wire mains cable replacement for authenticity, I'm going with the ground wire free version here and keep an eye on the various screws; so as to not expose anything "live" to the outside.
Yes, there will... But at the moment, the project was on hold for getting a few spare parts in order. The case needs finishing touches and the am/fm sections need testung and then alignment. I think it's too little for three parts, so I have to wait with part two until I'm done. Post vacation in October is my best guess
Hi! Any chance of doing a Denon Auto-Reverse Cassette Deck Mechanism by any chance? I've been stuck with the Auto-Reverse Mechanics from a Denon DF-07 Component System for over a year and one of your superb videos showing the dismantling and lubrication/reassembly of one of these would be a great help to me, practically every one of these Denon Cassette Decks for sale on eBay has a mechanical fault! (The Denon DRR-M33 has the same mechanism!) Chris Williams
Thanks for the kind words! As for auto reverse mechanisms... I don't have anyting along those lines in my queue. I might eventually, but the exact model depends on availability and affordablility 😊
I think you could have a nice audience without the voice and caricatures. I believe you have good content, it just seems as if your delivering to kids. Sorry if this hurts your feelings, but just giving my opinion. Thanks
I think of it more like letting a Muppet-style presenter do the talking; sadly, it is not uncommon to equate a certain style or technique with childrens entertainment, but that is just not the case; and I see it as a bit of a unique element in an otherwise totally saturated "market".
You deserve a medal for taking that on. I would have called it a basket case and chucked it in the bin and told my friend it got lost in the post 😜. You never cease to amaze me as to what you are prepared to take on.
Well, originally I just wanted to do some cleanup and fix that busted corner... but it snowballed from there, and it does make for an interesting video project.
@@atkelar It is that indeed.
Hi!
. . .It amazes me just how these sets were put together in the factory in the first place, especially the inaccessible wave change switch mechanism!
. . .I had a Telefunken "Magnetophon 55" to repair for a Vintage Radio Forum Member, and I traced intermittent loss of playback volume to a defective R/P switch contact in the grid circuit of the EL95 replay output valve, but seeing the forest of wiring and components attached to this switch assembly, desoldering and removing them all to fit the spare switch contact assembly I had simply wasn't on, so I bypassed it with a 0.1 μ capacitor to maintain the signal path on replay, then if I see the unit again, I can let the owner know in the future that the whole R/P switch contact assembly may need replacing which is a big job!
That looks a titanic task
You know your radio is old when 3 out of the 4 knobs and the entire pre-printed list of radio stations have nothing but static on their spectrum anymore, and the 4th is pretty much digital by now. :D
A beautiful project.
Then it is not only old but either broken or no antenna is connected :)
There are still some SW stations and MW is often packed full in the evening.
You need a better antenna, there are still zijn things out there.
Digital as in On and Off 😂
Nice soundtrack, not as depressing as some of your choices of late
nice music choices this time mate, much more up beat and in the vibe of your og track.
Nice!
I have the same model waiting in my shop.
That cabinet wood came up really well - it was quite a jump from 'scraping off the coating' to the sanded cabinet top!
There wasn't really much between anyway: it scraped off pretty clean, except the few spots where I accidentally scraped the wood and had to apply the putty.
That reminds me of my loewe opta bella,that is waiting for revival,the housing is needed repainting,but maybe i get the Chassis working😂
The good Thing is,i have the older Version, with a rectifier tube,which is easier to replace.
WOW!
. . .I thought you might have got the OpenScad out to design and print a new front bezel in 3D for it!
. . .How do you work out where all the components go? - do you have an Original Loewe-Opta Factory Manual to work from?
. . .Another thought has occurred to me - when you do a full restoration on an old set like this with many components having to be dismantled, cleaned and serviced and/or replaced, wouldn't you have to completely re-align the circuits with a.m. and f.m. radio Signal Generators afterwards?
Chris Williams
The schematic for the model is out there, yes. The "remake a new bezel" option was my second option, but that putty stuff holds up surprisingly well.
The alignment is on my to do list, yes. I doubt it will be far off from nominal though, as all the frequency critical capacitors are ceramic ones, and those are still good. Also the coils won't drift at all. But some of the tuning lugs are stuck in the coils, and to get them out without damage is my current hurdle.
I've missed a few episodes,, but nice soundtrack.
2:00 This speaker plug also fits into the mains socket. 4mm connector 19mm spacing. Never mix these up, the speaker only has a few ohms and will certainly be destroyed by AC 230V.
This happened to a friend of mine.
Yeah, these old banana style plugs sure fit the power sockets nicely. I'm using some of my test leads from my insulation transformer outlet quite regularly. Sadly, more modern devices come with these stupid sleeves over the plug, so the new wires won't fit the old plugs...
Great! Thxs! Waiting for continuation
The nicotine coating on the components is quite mild.
Used to hate working on TV's from heivey smokers households. Everything coated in a horrible thick tar, ash and dust mix. There were a couple of occasions where I did refuse to work on them because they were so bad.
Smoking and open fireplaces are not friendly to domestic appliances.
at least a fire place isn't sticky You still get it doing PC work
I've begun studying the isolator board. I intend to check the passives. Did you follow the ack signal paths to find the bad inverter? Did you use extender boards to access the pcb?
I don't have an extender PCB; but for troubleshooting, I left all the shielding off and had the left side panel removed too, that gave me a bit of access to the test points and quite a few components. As for the inverter: it wasn't related to the ACK signal, that one worked on my side, just pointing out that these TTL chips can go bad in general. But what you could do to find out which board is at fault: Remove all PCBs except the controller and isolator. Hook up the "ACK" line on a scope; I'd use the controller input for that, seems to be the best accessible. Then, one by one, add the cards and power on. During power on, the controller talks to all of the cards, one by one and expects an ACK signal, so you should see one from the current card. The only exception AFAIK are the oscillator and the high voltage ones, but those should also not give the Err6 on startup for that reason. They only say Err6 when requested by an output. That way, at least you know which card isn't doing the power on reply.
o)❤
I'm not sure which bella you have, there are multiple models, but looking at schematics, the chassis are not floating, i can also see stuff grounded to the chassis in the video.
Ah! It's a 4705W - and with "floating" I meant "with respect to mains input", sorry if that wasn't worded proper. The chassis is certainly the ground of the whole thing, just not "mains earth". The original didn't have a grounding wire to begin with. There's just a capacitor connecting one side of the input to the chassis, which I replaced with a "Y" class capacitor by now. But the mains earth should normally not be connected to the chassis. I think that might interfer with some antenna setups which are grounded at the antenna side, but that's just a hunch...
@@atkelar unless I am mistaken floating would be when you have a transformerless radio where the neutral or worse the hot wire is not connected to the chassis at all, but has its own bus write often called B-.
This set has a mains transformer, bridge rectifier and antenna ground lug all connect to ground directly. Every voltage in it is with respect to the ground so it's not floating.
In olden days people would connect antenna ground to a pipe from a radiator or something. But that's messy. And who has an antenna these days? The ground in the mains cable makes the chassis a little safer and it provides a ground for the antenna if your electricity installation is correct. I have grounded every radio with a mains transformer I ever worked on.
But don't take some comments word for it, ask on tube radio forums. You should get more or less the same answer. Some purist don't connect the ground wire because it's not original, but those are people with antennas on the roof and a ground pin for the antenna.
If you're worried it affects performance somehow, just run it with and without the earth wire connected.
I'll repeat my earlier warning that this goes out the window for sets without a mains transformer.
Oh, I'm pretty sure the transformerless versions are called "hot chassis" because they are directly connected to one pin of the outlet. Ideally neutral, but with non polarized plugs it could be either. "floating" has been used in all contexts I've seen to indicate that there's no set voltage (electrical potential) assosicated with it, at least from a given perspective. So from the mains outlet perspective, the chassis is "floating" and you shouldn't be able to measure any voltage between the outlet and the chassis. From the perspective of the secondary side, it's of course connected as the ground line (and in this case also one line of the heater string)
To me, the question whether or not to ground the chassis is mostly: What plug do I want? If I put in a three-wire connection, I naturally also ground the chassis for good measure. But since I was provided with a two wire mains cable replacement for authenticity, I'm going with the ground wire free version here and keep an eye on the various screws; so as to not expose anything "live" to the outside.
Will there be a part 2 of this Loewe-Opta "Bella"?
Yes, there will... But at the moment, the project was on hold for getting a few spare parts in order. The case needs finishing touches and the am/fm sections need testung and then alignment. I think it's too little for three parts, so I have to wait with part two until I'm done. Post vacation in October is my best guess
Hi!
Any chance of doing a Denon Auto-Reverse Cassette Deck Mechanism by any chance?
I've been stuck with the Auto-Reverse Mechanics from a Denon DF-07 Component System for over a year and one of your superb videos showing the dismantling and lubrication/reassembly of one of these would be a great help to me, practically every one of these Denon Cassette Decks for sale on eBay has a mechanical fault!
(The Denon DRR-M33 has the same mechanism!)
Chris Williams
Thanks for the kind words! As for auto reverse mechanisms... I don't have anyting along those lines in my queue. I might eventually, but the exact model depends on availability and affordablility 😊
What is this device, 🤔😸
An old valve based radio receiver, the keys are
OFF - _L_ong Wave - _M_edium Wave - Short (=_K_urz) Wave - _U_ltrashort Wave
...and if you push "LW" and "MW" together, it's the "Phono" input - hence the split symbol in the middle. I haven't seen that logic before...
It's a radio.
@@atkelar That is super cute actually. Terrible UX, but cute. :D
@@atkelar Oh, didn't see _that_!
Yikes, That was a tacky old radio for sure, but if someone gonna fix it in the end it gonna be you
I hope you cleaned you paws afterwards :)
Hi, are you still use your tigress email. I tried to send you a email. Rgds R
I think I got that. I'm just rotating with "to do" items, so replying is a bit of a hit and miss right now, sorry 😿
I think you could have a nice audience without the voice and caricatures. I believe you have good content, it just seems as if your delivering to kids. Sorry if this hurts your feelings, but just giving my opinion. Thanks
I think of it more like letting a Muppet-style presenter do the talking; sadly, it is not uncommon to equate a certain style or technique with childrens entertainment, but that is just not the case; and I see it as a bit of a unique element in an otherwise totally saturated "market".