First Vintage TV - 1961 Perdio Portarama

[Cameron]

I've just purchased my first foray into the world of vintage televisions! I spotted this in an antique shop and fell for the styling straight away. I have a classic caravan from 1960 which I'd like to have the TV up and running to use as a display prop. Of course I appreciate that it will no longer work independently without a digital receiver.

I've restored a few record players and reel to reel decks before, so I'm not totally new to this, but what should I be looking for before I power it up? It was sold as untested, with the glass 0.5A fuse inside pulled out. It has a virtually new 13amp plug on it, so I'm guessing it's been powered up fairly recently. I have the power lead (but I'm missing the battery lead) and have familiarised myself with what all the buttons do thanks to a wiring diagram I found for it online. I've also taken the case off to inspect for any obvious damage, but can't see anything.

Any tips greatly appreciated.
Regards,
Cameron.

[matspar]

Hi Cameron,

Welcome to the wonderful world of vintage TV!

The Perdio Portarama is a very popular and collectable little set. One of the first 12v all transistor sets so quite a landmark receiver. You'll find tons of info about these online and plenty of previous restorations on the forum.

Usual rules apply when powering up. Pay close attention to the power supply and mains input area and make sure nothing is visibly wrong, such as bulging electrolytics or signs of damp / missing components / previous repairs or any evidence of distress. Do some cold checks with a meter to make sure there's no dead shorts across the mains.

If your not happy or alarm bells are ringing don't plug it in just yet. If you go ahead and hit it with full mains be prepared for a sudden switch off in case it starts to sweat! If you have access to a variac run it up slowly on this. The presence of new plug means someone has been here very recently so you may find some work has already been carried out.

Some pics would be good to get an idea of the condition. Good luck!

Matt

[Graham G3ZVT]

I first encountered one of these sets when my parents took me on holiday to a cabin cruiser on the Norfolk Broads. The 12V supply came out of a 15A (maybe 5A) round pin socket. Earth pin was -ve neutral was +ve, I suppose it was a standard of the time.

Later on I got one of my own, when it went faulty I remember unsuccessfully trying to repair it, then I am sorry to say, it got dumped. If I remember correctly it had one thermionic device other than the CRT, the EHT diode.

[ukcol]

Hi Cameron,

Sadly I am going to be very negative right from the start for a number of reasons. (Sorry )

1] A Perdio Portarama is probably not the most suitable first TV restoration project.

2] Hope and pray that you are wrong about it having been powered up recently. If it has there is a very good chance that it has suffered serious damage (see below)

3] You will need more than a digital receiver to supply a signal to a working Portarama. The set uses the old 405 television system that started in 1936 and finally shut down in the 1980s. You will need a standards converter like the Aurora.

Before doing any work on the set give it a good visual inspection for signs of burnt components or physical damage.

The power supply for this set employs an 11.6v linear regulator, see the snip below.




If I haven't put you off completely yet, check the CRT heater with an ohmmeter for continuity. If a power supply fault has blown the CRT heater you may as well stop there.

If the CRT heater is OK the next thing is to examine the power supply. Test the transistor junctions with a DMM on the diode range. Also check the bridge rectifier for shorts.

Check the mains transformer for signs of past distress or shorts.

If all checks OK and not before, proceed as below.

For the first power up remove all the fuses except the 500mA mains fuse (F1). Use (say) a 25 ohm 10 watt W/W resistor for a dummy load and connect it across across the power supplies DC output. The resistor does not present a full load to the power supply but there must be some load or you will get incorrect voltage readings at the power supply output.

Apply mains power via a lamp limiter. If you have not used a lamp limiter before then search this forum for "lamp limiter" using the dialogue box at the top of this page. If the lamp lights to full brightness there is a problem that must be investigated first.

If all is well apply mains to the set directly (still using the dummy load) and measure the output of the power supply which should be about 11.5 volts. Any deviation from 11.5 volts that cannot be corrected by a small adjustment of the "Set HT" pot needs to be investigated.
If you get this far ask again about proceeding further.

[Sideband]

Absolutely great little sets but you'll need more than a digital receiver to see anything....you'll also need a standards converter as it's 405 only. It was the first all transistor (with the exception of the EHT rectifier) TV available in the UK. It's not the easiest of sets to work on although the MkII had been improved in this respect. I have a MkII and it gives a really superb picture via an Aurora standards converter and a digital receiver. I had to do quite a lot of work to mine to bring it up to standard and it is a bit of a 'rats nest' inside particularly with respect to the power supply section. I wouldn't recommend them as a 'first time' foray into vintage TV. The circuit is simple enough but the actual construction and location of some parts makes working on them less than straightforward.

[Sideband]

Originally Posted by ukcol

If all checks OK and not before, proceed as below.

For the first power up remove all the fuses except the 500mA mains fuse (F1). Use (say) a 25 ohm 10 watt W/W resistor for a dummy load and connect it across across the power supplies DC output. The resistor does not present a full load to the power supply but there must be some load or you will get incorrect voltage readings at the power supply output.

Apply mains power via a lamp limiter. If you have not used a lamp limiter before then search this forum for "lamp limiter" using the dialogue box at the top of this page. If the lamp lights to full brightness there is a problem that must be investigated first.

If all is well apply mains to the set directly (still using the dummy load) and measure the output of the power supply which should be about 11.5 volts. Any deviation from 11.5 volts that cannot be corrected by a small adjustment of the "Set HT" pot needs to be investigated.
If you get this far ask again about proceeding further.

I would add that part of the initial test (after confirming the CRT heater is OK) would be to carry out power supply checks with the CRT base removed. That way if the power supply does decide to output more than 11.5 volts (sometime much more) then the CRT won't be ruined.

Other than that, ukcol says it all.....!

[Cameron]

Thanks for all your replies.

I'm not sure how to add photos to the threads, can anyone advise?

Nothing looks amiss inside, it looks immaculate inside and out. There's not even any discolouration to the plastic. There was just some dust build up in the bottom of the case. The only thing that slightly concerns me is the is there's some slight warping to the case on the top right side as you look at the set, next to the handle, possibly caused from excess heat inside, though there's no component directly below the warp.

There's no evidence of any interference other than the 0.5a fuse being left loose in the rear compartment, which makes me assume that there could be a problem as discovered by the last person that plugged it in. No bulging electrolytics or burnt out transistors that I can see visually.

I don't have a lamp limiter though I do have a continuity meter to check a few things. I do admit I feel a little put off now! TVs seem somewhat a minefield compared to what I'm used to! Does anyone in Derbyshire/Nottinghamshire repair these?

[ukcol]

Originally Posted by Sideband

I would add that part of the initial test (after confirming the CRT heater is OK) would be to carry out power supply checks with the CRT base removed. That way if the power supply does decide to output more than 11.5 volts (sometime much more) then the CRT won't be ruined.

Pulling those 3 fuses will ensure the CRT heater is protected but pulling the base of the CRT is a good idea anyway.

Originally Posted by Cameron

I do admit I feel a little put off now!

Yes, I'm sorry about that Cameron but I wanted to make sure you knew what you were letting yourself in for.

[Cobaltblue]

Originally Posted by Cameron

I'm not sure how to add photos to the threads, can anyone advise?

When you click on Reply to Thread scroll down a bit you will see a Manage Attachments tab click on that a new window will open browse to your picture hit upload.

The Forum software will resize your pictures or you can do it yourself.

Cheers

Mike T

[Sideband]

Originally Posted by Cameron

I do admit I feel a little put off now! TVs seem somewhat a minefield compared to what I'm used to!

No reason why you can't restore the set with care and patience...it just isn't a good set to start with. The AF11x transistors used in the IF stages are notorious for giving intermittent faults. They can be replaced by the AF12x types as direct replacements (with the exception of the AF118 video output transistor) but they are getting expensive.

The line output transistor is delicate and (in the Mk I version) is difficult to get at and replace. The MkII is much easier in this respect. When I say delicate, not physically but electrically and won't take any abuse.

Anyway best thing to do is to assess the set yourself as far as you can and then decide whether to proceed or let someone else do it. Hopefully we'll see some pictures soon but don't forget you WILL need a standards converter as well as a digital STB to see anything....!

[ukcol]

Originally Posted by Sideband

Anyway best thing to do is to assess the set yourself as far as you can and then decide whether to proceed or let someone else do it.

There may be a halfway house; if there is a forum member in your area that is willing to work - with you - on the set. A long shot but worth asking.

[Boom]

Originally Posted by Cameron

I don't have a lamp limiter though I do have a continuity meter to check a few things.

That suggests that you don't have a test meter. You won't get far without one.

[Studio263]

Not an easy set for a beginner this one... I restored one last year and they really do cause head scratching, even for superficially basic faults. Mistakes tend to ruin transistors, most of which are pretty exotic and used at the limits of their specifications. Lovely results when working, but it can be a steep hill to climb.

A factor which is not always appreciated with the Portarama is that the scan coils are DC coupled to the line output stage. This means that if the line output transistor fails (which it often does) the scan coils will get ruined if the set isn't switched off right away. Therefore before you start it is important to check that the windings are not burned, the line ones are on the inside so the tube will have to come out (not a difficult as it first looks) and the coils will have to come off the neck. The scan coils are special low impedance / high sensitivity ones made just for transistor sets, ones from a bigger model won't do.

You won't get the original line output transistors any more but an AU113 works, they were used in quite a few early 1970s 12" mono portables and so are fairly easy to come by.

With the tube out, it is wise to check the various smoothing capacitors connected with the LT supply, if any of them are weak you'll get odd faults like lack of height, poor sync, AGC issues etc.

All kinds of faults will be caused if the batteries were stored in the set for any length of time; the corrosive fumes rot away the windings of the IF (etc) coils ruinously, there's no easy way back from that one. If the metalwork at the back looks at all crusty or stained check this before getting too involved.

The circuit around the video output stage is interesting, this is the hardest bit to design in a set which uses PNP transistors and a negative power supply rail.

As I mentioned, I'd say that dealing with one of these is no task for a beginner and it may be sensible to put it on one side until more experience and gear is gained. A BRC 980 or a Philips TVette 11 would be a better bet if you like small sets, both are easier to learn on.

[FERNSEH]

Studio263 wrote: "Not an easy set for a beginner this one...."

Agreed, this receiver employs germanium transistors which are not so forgiving to servicing mistakes as the later silicon types.

Attachment shows two Mark two Portarama TVs which I will sometime in the future get around to restoring. The other set is a Philco Safari, made in 1959.

DFWB.

[AidanLunn]

Not having had one of these I can't speak from practical experience but from looking at the service information, I echo the comments above.

As you're fairly local, I have a Marconi-branded 12" black and white portable using the Thorn 1590 chassis from about 10 years after your Perdio (1972/73) going FOC, if you want it? They are solid-state sets but infinitely easier to work on and get going than a PP would be for someone just beginning the hobby. The Marconi hasn't been switched on or worked on by myself at all, I got it as an unwanted addition to another Marconi 12" TV from the same time using the much rarer hybirid 1580 chassis (which you'd have to prize out of my cold, dead hands! )

It's in storage at the moment so I can't take a photo of it, but here's a picture of another example of the same model.

http://forum.radios-tv.co.uk/viewtopic.php?f=5&t=4055

Please note I am intermittently online, so if you PM me, I may not reply for a day or two.

Many thanks,
Aidan Lunn

[Cameron]

As promised, here are some photos of my Portarama. I'll have to split this over a couple of comments as I can only upload five photos at a time. Thanks Cobaltblue for advising how to upload the photos!

As you can see, cosmetically the outside case is very good, apart from the warp to the right of the handle as you look at the screen.

[Cameron]

And here's the inside of the set.

I'm feeling quite deflated about this now. I bought it to go in my classic caravan from 1960 which is styled to suit the whole Mid-Century/Atomic style that this TV set personifies. It's even the same hues of grey inside so when I saw this Portarama, I couldn't leave the shop without it. I'm going to search the web for any TV restorers near Nottingham/Derby (which is where I live now, I can't seem to change my bio from Leeds where I used to live) and see if I can get it up and running. It's only a bit of fun really, but it will really add to the caravan when we display it at shows. If I can get the TV working, that would just be the icing on the cake. I don't have a clue what I'm talking about when it comes to TVs, record players are far easier to repair! So perhaps this one is best left to the experts as I don't intend on making a habit of collecting old televisions!

[Cameron]

Originally Posted by AidanLunn

As you're fairly local, I have a Marconi-branded 12" black and white portable using the Thorn 1590 chassis from about 10 years after your Perdio (1972/73) going FOC, if you want it?

Thanks Aidan, that's really kind of you. But like I said in my comment above, I have my heart set on this Portarama as it's exactly what I'm looking for! Sadly the Marconi looks too modern for putting in my classic caravan. Thank you for the offer anyway

[ukcol]

Originally Posted by Cameron

I'm going to search the web for any TV restorers near Nottingham/Derby......

Post a request in this section - -

https://www.vintage-radio.net/forum/...play.php?f=145

Entitle your thread something like "Help with Perdio Panarama repair Nottingham/Derby" - its worth a punt.

[1100 man]

Originally Posted by Cameron

And here's the inside of the set.

I'm feeling quite deflated about this now. I bought it to go in my classic caravan from 1960 which is styled to suit the whole Mid-Century/Atomic style that this TV set personifies. It's even the same hues of grey inside so when I saw this Portarama, I couldn't leave the shop without it. I'm going to search the web for any TV restorers near Nottingham/Derby. So perhaps this one is best left to the experts as I don't intend on making a habit of collecting old televisions!

Hi Cameron,
Don't forget even if you do find someone to repair this TV for you, you will still need a standards converter to display any pictures or you will just have a blank screen! These are about £200 (a real bargain!!) which for a one off TV and a bit of fun is a big addition to the cost of getting it repaired!
I hope you do find a solution though as I can understand why you want the set.
All the best
Nick