Help with Invicta valve set - UK Vintage Radio Repair and Restoration Discussion Forum

LXSTEIN45 · 11th Aug 2020, 8:12 pm

Hi,
Been given this Invictus valve set to play with. It is an old bakelite mains driven set (dropper resistor) and I wonder if anyone might recognise the model so I can find a diagram for it?

Photos were a bit of an afterthought, I wanted to attempt a cleanup as it is very sticky, I assume a combination of vigh voltage, wax caps and probably a once smokey atmosphere!

It has 5 valves and will get a pic of the back end if that helps.

Gridiron · 11th Aug 2020, 8:27 pm

Invicta Model 200 (According to "Radio Radio" identical to Pye Model 47X).

LXSTEIN45 · 11th Aug 2020, 8:37 pm

Thank you sir!

AC/HL · 11th Aug 2020, 10:48 pm

Here: https://www.service-data.com/section.php/3937/1/200

LXSTEIN45 · 12th Aug 2020, 3:42 pm

Would anyone mind offering some advice please?

Graham G3ZVT · 12th Aug 2020, 4:00 pm

At last!
The radio on our kitchen shelf for the first 7 or so years of my life,
I had no idea of the make & model until now, just a vague memory.

Thanks guys.

12th Aug 2020, 4:14 pm

Quote:

Would anyone mind offering some advice please?

Apart from the usual change all waxies and check resistors not much really and of course switch cleaner!

Graham G3ZVT · 12th Aug 2020, 4:34 pm

Looking at the Radio Museum circuit, change the three electrolytic caps, one is prominent on your picture and the other two are mounted on the speaker.
More pictures in this thread
https://www.vintage-radio.net/forum/...d.php?t=152716

Change the tubular wax capacitors, but leave the flat ones undisturbed.

C23 on the RM sheet is "That Capacitor" change this as a priority.

Are you aware of the safety issues when working on live chassis sets?

LXSTEIN45 · 12th Aug 2020, 4:52 pm

Ta Graham. I was going to replace all the waxy's tbh.

Couple of the Q's I wanted to ask. There appears to be no filter on my radio C27/28 & L7 and wonder if this might have been ripped out when it was rewired or if some radios just didn't have them?

Also, R16 in my exaple compromises two 12ishk resistors in parallel. on that very diagram it is a 15k. I was going to replace this with a 15k 3w resitor.

Some of my resistors are a little high too so will replace them all. I assume unless stated 1/2 watt metal film should be adequate?

AC/HL · 12th Aug 2020, 4:58 pm

It's slightly unusual in being permeability tuned. Be careful with the soldering iron!

LXSTEIN45 · 12th Aug 2020, 7:21 pm

I am trying not to disturb the mica caps but I was expecting to have to re-align tbh!

This is my first valve radio restoration though. I have done many amps previously but radios have generally not needed touching in the past other than simple straightforward faults!

12th Aug 2020, 9:28 pm

Quote:

but I was expecting to have to re-align tbh!

To get "out of the box" performance it may be necessary (emphasis on the may) otherwise if it gets radio stations well there is no need.

MurphyNut · 13th Aug 2020, 9:21 am

I have one of these though mine is the Pye version, this might be of interest-

https://www.vintage-radio.net/forum/...d.php?t=165649

PJL · 13th Aug 2020, 10:00 am

The canned electrolytics used for HT reservoir and smoothing are pretty reliable so I would not replace these unless you have confirmed they are faulty. You should bring them gently back to life using a basic capacitor reformer.

Gabe001 · 13th Aug 2020, 11:13 am

If you, like me, don't have a capacitor reformer there is a post on a cossor 464 thread which explains how to do this. I'm posting a screenshot for you for reference.
I always use a lamp limiter for the initial switch on, it helps me control the voltage better amongst other things

LXSTEIN45 · 13th Aug 2020, 3:37 pm

Quote:

Originally Posted by MurphyNut

I have one of these though mine is the pye version, this might be of interest-

I had been there already. You did a cracking job! Can you comment on the input filter I mention above, along with the two resistors in parallel?

Just waiting for my Farnell order to arrive. Was a bit dissapointed with RS's availability of reasonably priced caps tbh!

LXSTEIN45 · 15th Aug 2020, 8:06 pm

Quote:

Originally Posted by Gabe001

If you, like me, don't have a capacitor reformer there is a post on a cossor 464 thread which explains how to do this. I'm posting a screenshot for you for reference.
I always use a lamp limiter for the initial switch on, it helps me control the voltage better amongst other things

Thank you for that. I suspect this has not been powered up for a number of years, so I will take a great deal of care when I get to do so!

LXSTEIN45 · 18th Aug 2020, 12:38 pm

Hi folks Manual says C19 .01 but looking at this cap it is 0.001u?

LXSTEIN45 · 18th Aug 2020, 4:25 pm

it's ok the marking was hiding behind some wax. ****** hell it's hard work replacing parts in these little radios!

unitelex · 18th Aug 2020, 6:30 pm

You can scrape the wax off with a screwdriver and the printing on the paper sleeve underneath becomes clear.

Since you are local to me you are welcome to do the alignment at my workshop if you have not got the equipment. I have a PLL sig generator.

Best Regards
Chris

11th Aug 2020, 8:12 pm	#1
LXSTEIN45 Hexode Join Date: Dec 2009 Location: South Manchester, UK. Posts: 262	Help with Invicta valve set Hi, Been given this Invictus valve set to play with. It is an old bakelite mains driven set (dropper resistor) and I wonder if anyone might recognise the model so I can find a diagram for it? Photos were a bit of an afterthought, I wanted to attempt a cleanup as it is very sticky, I assume a combination of vigh voltage, wax caps and probably a once smokey atmosphere! It has 5 valves and will get a pic of the back end if that helps. Attached Thumbnails

11th Aug 2020, 8:27 pm	#2
Gridiron Heptode Join Date: Apr 2010 Location: West Midlands, UK. Posts: 663	Re: Help with Invictus valve set Invicta Model 200 (According to "Radio Radio" identical to Pye Model 47X).

11th Aug 2020, 8:37 pm	#3
LXSTEIN45 Hexode Join Date: Dec 2009 Location: South Manchester, UK. Posts: 262	Re: Help with Invictus valve set Thank you sir!

11th Aug 2020, 10:48 pm	#4
AC/HL Dekatron Join Date: Nov 2003 Location: Heckmondwike, West Yorkshire, UK. Posts: 9,642	Re: Help with Invicta valve set Here: https://www.service-data.com/section.php/3937/1/200

12th Aug 2020, 3:42 pm	#5
LXSTEIN45 Hexode Join Date: Dec 2009 Location: South Manchester, UK. Posts: 262	Re: Help with Invicta valve set Would anyone mind offering some advice please?

12th Aug 2020, 4:00 pm	#6
Graham G3ZVT Dekatron Join Date: May 2010 Location: Greater Manchester, UK. Posts: 18,724	Re: Help with Invicta valve set At last! The radio on our kitchen shelf for the first 7 or so years of my life, I had no idea of the make & model until now, just a vague memory. Thanks guys. __________________ -- Graham. G3ZVT

12th Aug 2020, 4:34 pm	#8
Graham G3ZVT Dekatron Join Date: May 2010 Location: Greater Manchester, UK. Posts: 18,724	Re: Help with Invicta valve set Looking at the Radio Museum circuit, change the three electrolytic caps, one is prominent on your picture and the other two are mounted on the speaker. More pictures in this thread https://www.vintage-radio.net/forum/...d.php?t=152716 Change the tubular wax capacitors, but leave the flat ones undisturbed. C23 on the RM sheet is "That Capacitor" change this as a priority. Are you aware of the safety issues when working on live chassis sets? __________________ -- Graham. G3ZVT

12th Aug 2020, 4:52 pm	#9
LXSTEIN45 Hexode Join Date: Dec 2009 Location: South Manchester, UK. Posts: 262	Re: Help with Invicta valve set Ta Graham. I was going to replace all the waxy's tbh. Couple of the Q's I wanted to ask. There appears to be no filter on my radio C27/28 & L7 and wonder if this might have been ripped out when it was rewired or if some radios just didn't have them? Also, R16 in my exaple compromises two 12ishk resistors in parallel. on that very diagram it is a 15k. I was going to replace this with a 15k 3w resitor. Some of my resistors are a little high too so will replace them all. I assume unless stated 1/2 watt metal film should be adequate?

12th Aug 2020, 4:58 pm	#10
AC/HL Dekatron Join Date: Nov 2003 Location: Heckmondwike, West Yorkshire, UK. Posts: 9,642	Re: Help with Invicta valve set It's slightly unusual in being permeability tuned. Be careful with the soldering iron!

12th Aug 2020, 7:21 pm	#11
LXSTEIN45 Hexode Join Date: Dec 2009 Location: South Manchester, UK. Posts: 262	Re: Help with Invicta valve set I am trying not to disturb the mica caps but I was expecting to have to re-align tbh! This is my first valve radio restoration though. I have done many amps previously but radios have generally not needed touching in the past other than simple straightforward faults!

13th Aug 2020, 9:21 am	#13
MurphyNut Heptode Join Date: Apr 2016 Location: Croxley Green, Hertfordshire, UK. Posts: 979	Re: Help with Invicta valve set I have one of these though mine is the Pye version, this might be of interest- https://www.vintage-radio.net/forum/...d.php?t=165649 __________________ Clive Last edited by MurphyNut; 13th Aug 2020 at 9:27 am.

13th Aug 2020, 10:00 am	#14
PJL Dekatron Join Date: Sep 2005 Location: Seaford, East Sussex, UK. Posts: 5,997	Re: Help with Invicta valve set The canned electrolytics used for HT reservoir and smoothing are pretty reliable so I would not replace these unless you have confirmed they are faulty. You should bring them gently back to life using a basic capacitor reformer.

13th Aug 2020, 11:13 am	#15
Gabe001 Octode Join Date: Oct 2019 Location: Stockport, Greater Manchester, UK. Posts: 1,646	Re: Help with Invicta valve set If you, like me, don't have a capacitor reformer there is a post on a cossor 464 thread which explains how to do this. I'm posting a screenshot for you for reference. I always use a lamp limiter for the initial switch on, it helps me control the voltage better amongst other things Attached Thumbnails

18th Aug 2020, 12:38 pm	#18
LXSTEIN45 Hexode Join Date: Dec 2009 Location: South Manchester, UK. Posts: 262	Re: Help with Invicta valve set Hi folks Manual says C19 .01 but looking at this cap it is 0.001u? Attached Thumbnails

18th Aug 2020, 4:25 pm	#19
LXSTEIN45 Hexode Join Date: Dec 2009 Location: South Manchester, UK. Posts: 262	Re: Help with Invicta valve set it's ok the marking was hiding behind some wax. ****** hell it's hard work replacing parts in these little radios!

18th Aug 2020, 6:30 pm	#20
unitelex Hexode Join Date: May 2005 Location: Greater Manchester, UK. Posts: 498	Re: Help with Invicta valve set You can scrape the wax off with a screwdriver and the printing on the paper sleeve underneath becomes clear. Since you are local to me you are welcome to do the alignment at my workshop if you have not got the equipment. I have a PLL sig generator. Best Regards Chris