ITT Polo radio - UK Vintage Radio Repair and Restoration Discussion Forum

Tractorfan · 17th Apr 2019, 3:55 pm

Hi,
Years ago I had an ITT-KB 'Euromarine' radio which was lost during the move to France. I quite missed it, and have since managed to obtain an ITT-Schaub Lorenz 'Polo' radio which is virtually identical apart from minor 'cosmetic' details.
However, I've just noticed that the FM band only goes up to 104MHz. Whereas my old Euromarine covered up to 108MHz.
The Polo is a German spec. set, and I'm wondering if the FM band in that country is specified as 88 to 104MHz, or is this an oddity of ITT?
Also, it has two SW bands (K1 and K2), where, I think, the Euromarine had one, but I'm not certain..
Thanks in advance.
Cheers, Pete.

dazzlevision · 17th Apr 2019, 4:33 pm

http://kbmuseum.org.uk/itt_images/ITT_Euro_Marine.jpg

crackle · 17th Apr 2019, 5:13 pm

From the 1975 ITT (UK) catalogue
http://www.kbmuseum.org.uk/Catalogue...gue_page24.jpg

Specification for the ITT Euromarine (UK version)

Click image for larger version

Name: ITT Euromarine.jpg
Views: 99
Size: 56.3 KB
ID: 181460

Specification for the ITT Polo Automatic 105

Click image for larger version

Name: ITT Polo auto 105.jpg
Views: 94
Size: 72.9 KB
ID: 181459

Mike

bobbyball · 17th Apr 2019, 9:10 pm

Just checked one of my two "Euro Marine" radios and it is as per the pictures, with FM only going as far as 104 MHz. The other set I can't get to just at the minute but I suspect that it is similar. Nice sets - made in Hong Kong as per the sticker but with the "tapped" bass enhancing volume control so often found in German designs. By the time this range of radios was being made, production in Hong Kong must have been much cheaper. The rest is of course history...

Tractorfan · 17th Apr 2019, 10:38 pm

Hi, and thanks for your replies.
Aha!, so the Euro Marine only went up to 104MHz as well. Something else I hadn't spotted way back then!
Another thing that I found out was that if the plastic slider on the AC mains input was slid upwards, another pin was exposed that allowed the radio to work on 110 volts mains. It was very handy on night shifts in a power station where the maintenance supplies were 110 volts.
Thanks again,
Cheers, Pete.

Tractorfan · 18th Apr 2019, 10:02 am

Hi,
I forgot to add yesterday that I once saw another version of this set with a white case and, I think, a red dial. That one was also on a flea market and, with hind sight, I should have bought it.
It seems to be one of those radios that have many guises.

Cheers, Pete.

orbanp1 · 18th Apr 2019, 3:12 pm

Hi Pete,

That is a really nice radio!
elektrotanya has an excellent quality factory service manual for that radio:https://elektrotanya.com/itt_schaub-.../download.html

If you want to increase the FM coverage to 108MHz it probably can be done just by adjusting the trimmer capacitors In the FM-tuner.
I was able to do that at two radios that also only went to 104MHz, I did not need to change any components.
You need to adjust the FM oscillator and modulator trimmer caps.
It does not hurt if you have an FM signal generator.
Start at first to adjust the oscillator trim cap, C314, at the top of the band.
I found it the safest to "chase out" the frequency slowly, in small steps.
Then double check/correct at the low end of the FM-band (88MHz) by adjusting L304.
If the trimmer does not allow you to reach the 108MHz frequency, change C313 from 20pF to 16pF - 18pF or so, and then adjust C314.
Once you are happy with the frequency coverage, adjust the modulator circuit, the C305 trimmer. For best tracking adjust the modulator circuit at 106MHz first, and then L302 at 90MHz. Again, if the trimmer does not give enough range, change C304 from 27pF to 22pF or so.
Then you can update the scale with "Letraset", hopefully you can still find that.
If you do not have an FM-generator you can use an accurate, synthesized FM receiver, and commercial stations, or a programmable FM-modulator, used for car radios.

Regards, Peter

Tractorfan · 18th Apr 2019, 4:41 pm

Hi,
And thanks, Peter, for the info. If I can tweak it as far as 106 and a bit Megs, I'll be happy. There's not much above that in Europe worth listening to, and I've got other radios that cover the full band.
The Polo is handy for travelling and was dirt cheap at 5 euros, so not really worth changing components. It just seemed odd to end the band at 104.
Cheers, Pete.

17th Apr 2019, 3:55 pm	#1
Tractorfan Dekatron Join Date: Mar 2008 Location: St. Frajou, l'Isle en Dodon, Haute Garonne, France.(Previously: Ellesmere Port, Cheshire, UK.) Posts: 3,182	ITT Polo radio Hi, Years ago I had an ITT-KB 'Euromarine' radio which was lost during the move to France. I quite missed it, and have since managed to obtain an ITT-Schaub Lorenz 'Polo' radio which is virtually identical apart from minor 'cosmetic' details. However, I've just noticed that the FM band only goes up to 104MHz. Whereas my old Euromarine covered up to 108MHz. The Polo is a German spec. set, and I'm wondering if the FM band in that country is specified as 88 to 104MHz, or is this an oddity of ITT? Also, it has two SW bands (K1 and K2), where, I think, the Euromarine had one, but I'm not certain.. Thanks in advance. Cheers, Pete. Attached Thumbnails __________________ "Hello?, Yes, I'm on the train, I might lose the signal soon as we're just going into a tunn..."

17th Apr 2019, 4:33 pm	#2
dazzlevision Dekatron Join Date: Sep 2003 Location: Near Swindon, North Wiltshire, UK. Posts: 3,608	Re: ITT Polo radio http://kbmuseum.org.uk/itt_images/ITT_Euro_Marine.jpg

17th Apr 2019, 5:13 pm	#3
crackle Rest in Peace Join Date: Mar 2011 Location: Basildon, Essex, UK. Posts: 4,100	Re: ITT Polo radio From the 1975 ITT (UK) catalogue http://www.kbmuseum.org.uk/Catalogue...gue_page24.jpg Specification for the ITT Euromarine (UK version) Specification for the ITT Polo Automatic 105 Mike Last edited by crackle; 17th Apr 2019 at 5:29 pm.

17th Apr 2019, 9:10 pm	#4
bobbyball Octode Join Date: Jul 2011 Location: Stockport, Greater Manchester Posts: 1,214	Re: ITT Polo radio Just checked one of my two "Euro Marine" radios and it is as per the pictures, with FM only going as far as 104 MHz. The other set I can't get to just at the minute but I suspect that it is similar. Nice sets - made in Hong Kong as per the sticker but with the "tapped" bass enhancing volume control so often found in German designs. By the time this range of radios was being made, production in Hong Kong must have been much cheaper. The rest is of course history... __________________ Robert

17th Apr 2019, 10:38 pm	#5
Tractorfan Dekatron Join Date: Mar 2008 Location: St. Frajou, l'Isle en Dodon, Haute Garonne, France.(Previously: Ellesmere Port, Cheshire, UK.) Posts: 3,182	Re: ITT Polo radio Hi, and thanks for your replies. Aha!, so the Euro Marine only went up to 104MHz as well. Something else I hadn't spotted way back then! Another thing that I found out was that if the plastic slider on the AC mains input was slid upwards, another pin was exposed that allowed the radio to work on 110 volts mains. It was very handy on night shifts in a power station where the maintenance supplies were 110 volts. Thanks again, Cheers, Pete. __________________ "Hello?, Yes, I'm on the train, I might lose the signal soon as we're just going into a tunn..."

18th Apr 2019, 10:02 am	#6
Tractorfan Dekatron Join Date: Mar 2008 Location: St. Frajou, l'Isle en Dodon, Haute Garonne, France.(Previously: Ellesmere Port, Cheshire, UK.) Posts: 3,182	Re: ITT Polo radio Hi, I forgot to add yesterday that I once saw another version of this set with a white case and, I think, a red dial. That one was also on a flea market and, with hind sight, I should have bought it. It seems to be one of those radios that have many guises. Cheers, Pete. __________________ "Hello?, Yes, I'm on the train, I might lose the signal soon as we're just going into a tunn..."

18th Apr 2019, 3:12 pm	#7
orbanp1 Heptode Join Date: Nov 2009 Location: London, Ontario, Canada Posts: 675	Re: ITT Polo radio Hi Pete, That is a really nice radio! elektrotanya has an excellent quality factory service manual for that radio:https://elektrotanya.com/itt_schaub-.../download.html If you want to increase the FM coverage to 108MHz it probably can be done just by adjusting the trimmer capacitors In the FM-tuner. I was able to do that at two radios that also only went to 104MHz, I did not need to change any components. You need to adjust the FM oscillator and modulator trimmer caps. It does not hurt if you have an FM signal generator. Start at first to adjust the oscillator trim cap, C314, at the top of the band. I found it the safest to "chase out" the frequency slowly, in small steps. Then double check/correct at the low end of the FM-band (88MHz) by adjusting L304. If the trimmer does not allow you to reach the 108MHz frequency, change C313 from 20pF to 16pF - 18pF or so, and then adjust C314. Once you are happy with the frequency coverage, adjust the modulator circuit, the C305 trimmer. For best tracking adjust the modulator circuit at 106MHz first, and then L302 at 90MHz. Again, if the trimmer does not give enough range, change C304 from 27pF to 22pF or so. Then you can update the scale with "Letraset", hopefully you can still find that. If you do not have an FM-generator you can use an accurate, synthesized FM receiver, and commercial stations, or a programmable FM-modulator, used for car radios. Regards, Peter

18th Apr 2019, 4:41 pm	#8
Tractorfan Dekatron Join Date: Mar 2008 Location: St. Frajou, l'Isle en Dodon, Haute Garonne, France.(Previously: Ellesmere Port, Cheshire, UK.) Posts: 3,182	Re: ITT Polo radio Hi, And thanks, Peter, for the info. If I can tweak it as far as 106 and a bit Megs, I'll be happy. There's not much above that in Europe worth listening to, and I've got other radios that cover the full band. The Polo is handy for travelling and was dirt cheap at 5 euros, so not really worth changing components. It just seemed odd to end the band at 104. Cheers, Pete. __________________ "Hello?, Yes, I'm on the train, I might lose the signal soon as we're just going into a tunn..."