g'day and welcome back today i've got a chrysler 11-99 i'm not sure what year this was made the exterior stay consistent but the interior changed the design inside changed a bit but it is a valve radio it's am only it's got a volume and on off switch and a tuning dial that's it the the dial doesn't look too bad it's reasonably clear that the plastic hasn't you know discolored and the dial looks alright but i can't move it it's frozen so i don't know if it's the dials back onto the plastic or what but they won't move this whole front panel is painted this color down here and this one here so they should clean up okay they look pretty good the rest of the case is quite yellow it's probably not showing up in the camera but if i lift this handle up here you can see that's the original color so it's quite yellow very yellow so i should be able to use the peroxide treatment on this and might come up nice i bought this back in 2019 i bought it in melbourne from a shoppers down at mornington somewhere it was a shed on the side of the road a dirty shed with a guy in there drinking something or i think he's drinking wine he wanted sixty dollars for it and i offered him 30 and i think he settled on about 40 or something now the idea of this size of radio was there was a kitchen radio and uh after breakfast mum would be washing the dishes you'd have the radio on and then she finished washing the dishes up the kids at school dad's going to work and she could pull the handling at the back here lift it up and take it out and do the laundry or wander out the garden it is powered by main supply there's no battery in it but you would just have to plug it in somewhere else now i'm guessing this is how you pull it apart this this is an earth screw as well so i've done these radios before not this model similar radios and they also had the earth and the antenna screws as part of the screws that hold the back on it's a little bit weird all right let's see if this back will come off all right there it comes so the back took a little bit of struggling to get out but anyway this is really dirty so it looks like it's got sawdust on it or something but it certainly doesn't look like it's been touched since 1970 odd now i noticed it's got a rectifier in it they later went to a silicon diode so it's a four valve set which is a bit unusual because they've moved away from reflex sets so whatever um anyway it it looks original it should be an easy fix actually looking at that now hang on i can see that's a 6g v8 so they're a dual valve so it's got a pentode and a triad built in so that'll be the preamp and the output valve in one amp they were pretty popular back at that time now that i know it's got the 6v4 rectifier and not the silicon diode in there i'll go and get the correct schematic for it i think i'll take it out into the workshop before i take it any further and just blow all this rubbish off and then i'll come back and pull it out of the case here i took it out of the shed and blew it out it did come up good it's clean there's a whistle in there and it appeared to be a sorter so maybe this ended up out in somebody's workshop somewhere i also downloaded the schematic there's nothing unusual in here 455 for the frequency of the if normal tuning range alignment conventional so they don't even tell you it's just everyone knows here's the schematic and here's that 6g v8 and there's the triad and the pentode so it's just one valve split so it's a one two three four five valve set this has got the 6v6 in it but it appears that there's no um schematic for the diode one anyway that's nicely done there it's got the ht2 hd1 the bias there look at that so nice and easy to read that's good i'll take the metal uh chassis out of the case there's some screws in there i think there's five the little booklet said all right the knob should pull off oh yeah there we go and this will simply unplug it's very loose it'll unscrew uh this little retaining screw is designed to push these little fingers out and jam it in the plastic there and after about 70 odd years i'm not sure what's going to want to come off again they don't seem to be gripping it maybe i'll try and turn it it might just sort of screw off there we go all i have to do is undo the five screws here and this should pop out okay all right all the screws are out should just pop out there we go all right they came out oh that's look at that that front panel came off oh terrific so i can keep that aside just clean it up a bit and i'll be done yeah look the bugs have eaten the speaker again so this must have been out in a workshop or garage or something somewhere it's covered in the sawdust and bugs have eaten it so it's been outside somewhere otherwise it looks alright looks good and the um there's the mounting for the capacitor they're good the rubber is excellent it's like a silicone-y kind of rubber a plastic rubber or something i'm not sure what it's called but um it's held together well let's have a look at the bottom well the bottom is very neat um got some fairly modern looking capacitors in there they're not very big uh what are they 40 microfarad that's not bad is it good size what's that one 20 microfarad 150 volts uh that's 150 volts too i've got about one two what six capacitors in there to change i'll change those of course that's it it'll be this will work and this will work for sure i'll plug it in we'll see what it does okay i've got an aerial on i've got it on dim bulb uh 140 i'll turn that down a little okay the mid 30 somewhere there we go here we go lights are on or the light here it is here but we have a lot of people that aren't on farms that are in units and duplexes that come here because they get that opportunity to have their children experience the farm single day exactly what i thought it's going to work perfectly so there's absolutely nothing to do okay that's very tight i could loosen that up by this stage of development these radios just work so well in minimum parts it's it's pretty good so it doesn't even sound like it's got any distortion so yeah it's looking good sounds like the pots losing contact right at the end there that's great yeah it's come good anyway so that fixed itself all right i'll just flip it over i'll do a couple of quick voltage checks just to for fun and then i'm going to replace the caps and we'll clean up the case uh here's the schematic in the power supply it's got a primary and just a single secondary there's no set of tap it's powering both anodes there so it's a half wave rectification the other end is going to ground through a 120 ohm resistor so that gives you a bias of -5 so for voltages we've got -5 110 and 80. easy so i've got to power up it's on full voltage i put it on full voltage it's working all right okay so pin 9 is the grid so i get on there it should be -5 it's minus four so that caps probably leaking a little bit now the other one was 80 on this small capacitor 78 and the large one here should have been 110 i think 109 there you go this is the six uh it's got 30 volts on 105 on number six so there's one it should be 30 volts 27.8 uh that'll do what i say number six there it is it should be 105 101 that'll do here's the if amp one should be 45 6 should be 80. so pin number one should be 45 47 and 1 2 3 4 5 6 should be eighty seventy seven if here's the er six and seven that's the mixer pin one's forty five then we've got seven and eight at eighty so that's pin one should be forty five forty seven and a seven and eight of these ones 77 they're supposed to be 80. okay good enough so all these voltages are pretty good and there's a little bit of hum so it'll be these two guys here i'll get rid of those the coupling cap may be leaking um 120 ohms there it is there hang on let's have a look at that that's dropping five volts so yeah it might be just leaking a little bit so what i'll do of course is i will change those capacitors they are likely to go short at any time if i just left them there i'll check all the resistors as i go anything over 10 to 20 percent i'll change and the rest of it i'll just do the peroxide treatment to the case i thought i'd start the capacitor replacement by changing these two electrolytics the 20 uf capacitor are replaced with a 22 uf at 200 volts and the 40 i'm going to replace with a 47 uf 200 volts that's the closest i can get to 40 unless i use a 33. before i change these two capacitors i thought i'd have a bit of fun i've set up a microphone and i thought i'll record the amount of hum and then compare it after i've replaced the capacitors so i've set up a little microphone on a tripod and i've got it a certain distance from the speaker which is this plastic spool and i'll turn the volume to minimum and it's tuned off station now the set's been warming up for about five minutes i'll record it now we'll see what it looks like well that reading is not too bad isn't it so we'll see what difference it makes with the new ones in i've replaced the two capacitors and they've come out quite neat they've mounted in very neatly i have the mic set up again and i measured it with a little plastic spool it's in exactly the same place now just going by the amount of hum i don't think it's any different i think those capacitors were perfect so i'll start the recorder here's the volume level with the old capacitors and here's the new ones there's not much difference is there well they're exactly the same so the old capacitor is probably working all right but here's the date stamp on them and that's 3168 so i'm assuming that's week 31 of 68 1968. anyway i was just having a bit of fun
but just shows that yukon made reasonably good capacitors in 68. i've changed the other caps here i checked all the resistors as i went around and they are all fine they were all within 10 so i'm going to leave those in there there's the casualty list not much at all on this radio so i replaced that coupling cap of course i want to check the voltage on the grid of the output valve i'll put it in dim bulb just to start it up i assume it's going to work i didn't do too much work to it bulb's not coming on i'll go to full power it's been about five minutes i've put it back to 240 volts there so i'll measure it here i think i can measure it there and i got 4.9 supposed to be five so it's come up about one volt after changing that coupling capacitor i guess that's what it was i didn't change the valve or any of the resistors so that's the only thing that's changed all right i've turned the radio over again and i'll just make sure it's working it's all warmed up still there's a bit of noise a bit of crackling going on there might be some dirt still in that tuning capacitor so i'll go and blow it out again now also it's really hard to turn and it's got a loose area so it'll be the bearings as the bearings roll back and forth and hit each other so you can turn it easy there then it gets tight so it'll be the little ball bearings in the front i'll clean them and grease them up and the volume control is tight too so i'll put a bit of oil down there and i'll see if i can get some grease into the capacitor there this is the front of the tuning capacitor looking through the pole in the front panel and these little ball bearings in there and they're pretty gummed up and black bit hard to see there but they're full of dried grease so i'm going to go outside in the workshop and i'll spray it with some degreaser or something to get it out there clean it up then i'll put some new grease in there for the volume control just put a bit of oil there and might get in there no it's getting it a little bit i'll let it sit for a bit put a bit more oil on it let it sit and uh oh that should that should work i took all this out to the shed and cleaned it all up i used a bit of degreaser on the bearings there and they cleaned up really nice so i'll give it a go yeah that's good i've put the power back on i want to see if that capacitor still crackles i brushed it out and sprayed it and blew it out some air from abc radio brisbane all right no sign of any crackling there the radios we can find i will check the if frequencies make sure that's right and i'll do that a bit later the next thing i want to look at is this speaker and the little holes in it i have a bit of masking tape here and i'm going to put it over the hole in the back of the speaker i'll get this as far down as i can the idea was that i put the tape on put some rubber cement in there then remove the tape later what i'm going to use is liquid electrical tape and it just dries like a piece of rubber so i should be able to paint it on here just like that and it'll form on the back of that masking tape and i should be able to peel the masking tape off later i did this on the normande radiogram speakers and that worked really well i think that'll do looks right it'll dry a bit flatter than what it is now i'll leave it for a couple of hours and see how it comes up i'm out in the workshop i was just going to start doing the retrobrite procedure on this plastic to try and get the yellow out i've thoroughly washed them and they've come up pretty good there's some little dots on the top here and i thought they were fly spots but i don't think they are i think this has been in a workshop and it's got some welding uh sparks on there and burnt it slightly so i'll try and sand them off so i've got some waterproof paper here this is 1200 grit in the european standard not sure what it would be in the us standard with maybe 400 or something and it's not doing much i've upgraded from the 1200 to 600 and i've no idea what that is in the american standard it's reasonably coarse it's not taking it off i'll just keep going a little bit i'm not going to get them out i've sanded this off pretty heavily this was badly affected this not so much there's still some little dots there i'm not going to go mad on it because it's just you might make it worse than what it is so i'm happy to leave it like that and i'll start doing the retrobrite process it looks like they've put a bit of clear lacquer over this made in australia the symbol on the back here so i'll just sand it off of the plastic here it was around in a circle there so if i left that on there i'd end up with a darker circle so i'll just sand it away yeah i think that's taken that off but i've cut a bit of masking tape out i'm going to put it over this symbol to hopefully keep the hydrogen peroxide out of there i've done this a number of times this is a hydrogen peroxide you get it from the chemist pharmacy or drugstore wherever you live and it's just for putting in your hair to blonde it up i suppose so all you do is put the peroxide on here and put it out in the sun in a plastic bag and it should take this brown off now the process is called retro bright it doesn't it's not really anybody's process it's just something some computer geeks came up with when they were trying to brighten up the cases from the 1970s computers so it's just picked up the name retrobrite there's a whole wikipedia article on it so if you want to read about it and it tells you all the different ways of doing it i live in queensland i'll just throw it out in the sun if you live in sweden or something like that you can put it in the oven you can put uv lights on it i believe it benefits from uv lights uh you can add laundry powder there's all sorts of different ways of doing it so all i've done is put a reasonably thick coating on it i have a vacuum sealed bag here this is a food saver bag whatever you want to call them you vacuum down packing your food in it so i'll pop it in there i'll take this inside i'll seal this end up and i'll just throw it out in the backyard for the day um it's a bit overcast today so i might actually have to do it for a couple of days i need to do these other two pieces then i'll put it out the backyard with this one i've sealed both of them up and i've left as much air as i can in there when i put them out in the sun they'll expand and the plastic bag will move away from the plastic case so again throw them on the back lawn now while the case is sitting outside i thought i'll paint this because it is a very creamy yellow color it's got that old age look about it i'm going to leave the bottom i'm happy with the bottom so i'll mask that off i'll have to mask this off and then i'll give it a spray paint now here's some paint it's called hogs bristle it's dulux and that's pretty close to the origin i think that'll be okay so i'll use that so to prepare for paint i'm just going to sit here and run steel wool up and down the grooves and just sort of rough it up a little bit with that and give it a spray paint and these paints go straight on the plastic they're terrific now i spent a fair bit of time just making sure this was spotlessly clean there's a couple little scratches i've sanded them out so i can give it a coat of paint now i've just given that a very light coat i'll give it another coat in about 10 minutes or so just maybe need three coats or something to get full coverage and that'll be done now i ended up giving this i think three coats it's been drying for uh quite a few hours now i'm just concerned that the paint might have bled through under the numbers but it hasn't it's good okay that's fine good let's take that off as well okay that needs a little bit more drying but it's gosh it's good it's it's you wouldn't know it's painted it was painted originally of course and this bits painted but you wouldn't know that was painted that looks great all right fantastic i'll let it dry off i just washed this this is the tuning dial and it's as clear as the day was made it's in great condition i'll just give it a quick polish with some plastics just to sort of take the dullness off it but here it's clear it hasn't gone yellow at all i put these out in the backyard two days ago and i took them in last night and put them out again this morning we got about 10 minutes of sun in those two days so they really haven't worked as well as they should have i don't know if you can see it that's kind of these it's brown there there's the original color there it's still brown and it's kind of blotchy too so i'm going to do it again i'll wait a couple of days till the sun comes out put them back in the bags i'm going to try again and we'll have a look after that i'm about to do the rf alignment and i've got a little bit of time so i thought i'll just lay out what i'm doing if you know all about this stuff just skip ahead so let's assume we've got a radio station over here it's got an antenna on the top it transmits a sinusoidal wave with the signal on top of it we'll say it's transmitting at 600 kilohertz our radio has an antenna on the top the antenna picks up the signal and we feed it into a coil which we call the antenna coil alongside the antenna coil is the tuning capacitor now when you have a coil and a capacitor you can make it resonate at a certain frequency it's called a tank circuit so to get the 600 kilohertz into a radio we tune that to 600 that's about 600 now that tank circuit's resonating at 600 and will pass the signal through to the radio so that's one of the adjustments we need to get that to resonate at 600 we have a second gang here and this is called the local oscillator that also has a coil and we make that resonate as well so this little tank circuit is self-oscillating it produces its own frequency the next in line is the mixer valve or the converter valve or the first detector whatever you want to call it and we're going to mix these two frequencies together so we've got 600 here our high f our intermediate frequency on this radio and it's fairly typical is 455. the 455 is what we're going to pass through the radio with the signal attached to the top of it we've got this tuned to 600 the radio station's coming through on 600 we need this to be 455 above that 600. so we need this to resonate at 1055.
so this is resonating at 600 this is 1055. we jumble it all together into the mixer or converter and we get four main signals out you'll get the 600 you put in you'll get the 1055. you'll get the addition of those two signals there which will be what 1655 and you'll also get the difference between those two and that'll be 455. we don't want these ones we want this one to do that we put in filters and they're called intermediate frequency transformers these are tank circuits similar to that they have a coil and a capacitor and we can adjust those so they resonate at 455.
so what comes out here is 455. we amplify it goes into another if we can adjust that so that also is 455 oops now this 455 signal is then sent off to the detector and the amp the amplifier section is called af or audio frequency this section up here this tuning section here is called rf for radio frequency and this section here is called if for intermediate frequency that's the frequency between the two now so what we're trying to achieve is this oscillator is set to the correct frequency when this one is set to the correct frequency so we need to set that at 600 we need to set that at 1055 and the pointer needs to point to 600 on the dial the first thing we've got to do is set the pointer up on the dial so let's set the dial on this one it would simply be the fact that this is horizontal now some radios may have a line on there or a mark or something others you just center so that looks pretty good let's move that a little bit all right now the second thing we do is put the dial on 600. and in this case because i don't have any markings on here as to the frequency i know 7zl in hobart is 600. i've got the generator on 600 there and because this is on zl that should come through loud and clear there i haven't put a meter on it i'll just do it by ear at this stage and it looks like it's a bit out there it is there all right here's the oscillator on the radio here's the oscillator we're looking at here and what's happening is the pointer is pointing to 600 or zl but this is not resonating at 1055. so we can change that resonant point by adjusting the screw on this one mine doesn't have the screw it has a slug in the middle like this one does but you have to turn it from inside with a slot in the top of the slack same thing though so what i'm going to do is reposition the pointer to zl and i'll adjust this slug up and down until we get it to peak so if i put my little adjuster in here find the slot there it is and i'll move that slightly towards the zl there so i know which way to turn this it's not helping it's getting further away here comes just turn it up a bit all right so that's now adjusted what that means now is this oscillator circuit is now oscillating at 10 55 with a pointer pointing to 600 the next step is to go up to the top end of the scale and we'll put it i'll put it on 1 500 you would normally do it about 14. i've got a marking for
3ak which is 1500 so i'm going to use 1500 there will be a trimmer to trim this end of the scale we don't adjust this again at the top end this is all done down the bottom so the cores are adjusted at the low frequency trimmers on the top i'll change the generator here make that 15 and i'll put the dial on 3ak which is 1500 it just says ak there of course there it is wow it's right on it so we don't need to adjust anything there i'll just turn it up make sure it's right it's perfect it's absolutely perfect so i don't need to adjust it i'll show you what i would have adjusted if i had to now this is what i would have used to adjust it if i needed to these are pretty much factory set but you can adjust them if you want to and i've done it on other radios but this is just the tube it has a wire running through the center of it it has another wire wrapped around the outside and all you do is wrap or unwrap wire on it to change its capacitance because this is spot on and as i said it's factory set they don't really expect you to do anything with it later in life but what you can do is if i change the capacitance of it by putting my finger on it and come back here i can retune that there it is there so i'll take my finger off goes back where it was if that had come up short of 3ak or 1500 i could have added some more wire backed onto it if it had overshot 1500 i could have taken a bit more off there's not much left on there so i wouldn't have been too keen mucking around with this one but it doesn't need to be adjusted anyway that's the trimmer for the oscillator now that's it for the oscillator part if we had to adjust the trimmer you would have to go back and just keep adjusting back and forth make sure that they stay the same when you adjust the trimmer you may impact the position down here so you just got to go back and forth to get it right at both ends so that means the oscillator section is now set up correctly so all we have to do now is make sure the antenna is on the same page so we go back to 600 with this pointer on 600 we adjust this cause for peak output this coil has an adjustment on the end we don't have that on this radio what we have is a loop stick antenna or a farad right antenna whatever you want to call it and you move the coil up and down on the ferrite rod now this has been glued in at the factory i'm not going to touch it but i still need to make sure that is resonating at 600 i've got the generator on 600 again i've got this set to zl which we know is 600 i've also connected my meter up so to find out if this is 600 what we do is use a procedure called rocking now the idea is that i move this away from 600 on the dial i follow it up by adjusting the oscillator down here and if i get a stronger signal then i know this isn't at 600 because i've moved away from 600 i have the meter on 30 on the top so if i move the dial away it drops off i'll follow it up with the oscillator and see if we can get better than 30 and we can lots better so that means that coil is not oscillating at 600. so i'll grab it further i think that's about it so how far off are we oh just a little bit it's not far is it i'll turn that down so decision time do i try and move this coil or do i move the dial to align with the zl or the 600 again the problem is if i move the dial and then somebody comes along and someday overruns it and just moves along a bit they'll set it up to neutral come back here and these will all be out it's not a big deal it'll only be out that much it's not huge all right i'm going to try and move this coil i'm hoping it's just a bit of wax on the end here perhaps try the other end as well i don't want to ruin the coil that'll be the last thing let's see if that'll move please okay cool i've repositioned the dial to the center of zl or 600 so i'll adjust the oscillator to maximum adjust this to maximum using my fingers which is going to affect it maximum so that's about it there i'll adjust the oscillator a little bit we're maximized everywhere okay we're still in the middle of zl that's maximized let's maximize i'll put a bit of something there to hold that and we're done it's got a little bit of wax there i'll just see if that'll melt in the wax is dried there and it's holding it quite well i've put the generator back on 1500 and i'll just go up and make sure we're still somewhere near 38k and the 1500 that's right in the middle of 38k so it's perfect all right we'll carry on with the rest of it we're going well we have the pointer set up we've got the low end of the oscillator setup we've got the high end of the oscillator setup and now we've got the low end of the radio frequency setup all we have to do is put it up to 1500 again there's a little trimmer capacitor on top of the radio tuner and we can trim this to just make the range that this capacitor here operates over longer or shorter and we adjust that so that it is exactly 455 away from this one and you do that simply by turning the trimmer and getting the peak output from this capacitor first thing of course is we put that on 1500 i'll put the dial back on 1500 or 38k there's a little trimmer on the top i'll just turn the volume up a bit okay now all we've got to do is rotate this to get the peak volume less more less and you would have to say that's exactly where it was so that's it it's pretty simple really it's just a matter of getting the pointer and these points to all line up with each other and you're done i hope that helped a little bit probably not the best instructor in the world but this is pretty easy once you work it out anyway i'm going to move on i'm going to put the radio back in the case right i've got all the parts for the case they're all cleaned up and ready to go together the hydrogen peroxide effort on this wasn't as good even after the second try and the back is a little blotchy in fact it's sort of blotchy all over and i think the problem was that the bag was sitting on it and because it wasn't hot enough it didn't balloon the bag out like it normally does and keep it away and i think that's what went wrong there but anyway it's not bad it's just not quite as good as it could be this front half has come out all right that looks quite respectable on the top and of course the the front panel the paint on there looks fantastic it's really good so i'll start assembling it now the first thing to do is put this front in here and then we put that on the radio so that should go in there there we go all right there's five screws to go back in and then i'll come back i've put the screws in i just got to put the back on i'll get rid of this cushion i'm going to attempt to put the back on again i struggle getting this apart you've got to get a fair angle on it i think to get it all clipped together oh my gosh there we go all right and put the two screws back in alright i need to put the dial on you'll remember that i had trouble with the dial hitting hard against the case and i couldn't move it so i've made up a little spacer here out of a bit of perspex so that it doesn't affect the light shining through and that'll keep it away from the case for me now i've got to get this on it's not easy because because it's got fingers on it they splay out it's very hard to get this on that's quite hard there we go all right i've got to line this up again of course so i'll just keep going until it lines up oops went too far about there i think that looks good a little cap to go in the top there all right and the last thing is the knob there we go all right it's warmed up i'll just put some volume on we'll just listen to it for a second 3.6 trillion us but the imf notes that climate-oriented funds only account for 130 billion us dollars so just a fraction of what you might expect play today responsibly of his 1-800-858-8885 uh pusher and danny shum he's got seven and it's the similar tail on the jockeys uh that burden has become a very important yeah so working really well it's still got a lot of hum it's only a half-wave rectifier um i think it needs bigger capacitors to get rid of that last bit of hum there anyway i'm not going to worry about it but it does have a little bit of hum when the volume is up you can't hear it of course this is a chrysler 1199 they made them from 1965 to 1974. now according to radio museum this is the last domestic valve operated radio that was marketed in australia so they hung into the end there and apparently people preferred the valve radios over transistors for a little while there's a bit of reluctance to change look it's come up pretty good i'm not over the moon with the finish but it's not that bad so you remember how brown it was originally so there's a difference now so that's the original color there and this is what the hydrogen peroxide has brought it back to so it's not too bad is it but it's still sort of got this brownie look about it so anyway well that's it i'll put this on display with the rest of them i quite like the design of this one this was a pretty easy repair and it was good for me while i'm on light duties i hope you enjoyed it and i hope you can join me for my next radio adventure it was a hot morning in florida at cape kennedy sitting in seat 32 row e of the press stand was reporter darren hinch of the sydney sun and mbs ready to go it's news to move and if you can hear the going to noise anything quite like this one you
2021-11-21