Hallicrafters S38 - UK Vintage Radio Repair and Restoration Discussion Forum

mickm3for · 17th Feb 2020, 12:12 pm

Hi i have this s38 it now works But the range 1 and 2 aerial coils are burnt they are black and open circuit do i dismantle (not an easy job ) and rewind or use cap coupling to top of tuned circuit , using this it seems rather deaf. What would you do please? Mick

HamishBoxer · 17th Feb 2020, 1:57 pm

Rewinding would of course be best.Wonder what caused the burn up.Just a thought ,could you fit replacements anywhere else?

G6Tanuki · 17th Feb 2020, 2:40 pm

If you can find a "full" manual for the receiver, it may include details of the coil inductances, which would make rewinding a bit easier.

As to why they've 'cooked', is it a live-chassis AC/DC receiver? If so, I wonder if it could have been wired with the chassis 'live', then the aerial was earthed and the coils got to pass mains-current?

Quite a few US radios tried to get round the 'live chassis' thing by using a negative-rail bus-bar which was not connected to the chassis except via a small RF-bypass capacitor (1000pF or so) and a parallel receiver (100K?) to act as a static-bleed. If the bus-bar is inadvertently shorted to the chassis, or the RF-bypass capacitor goes short-circuit, it can lead to the antenna-coil being zapped,.

g4aaw pete · 17th Feb 2020, 5:57 pm

The manual here for the S38B seems to have coil info

http://www.radiosurplus.it/pdf/S-38B.pdf

mickm3for · 17th Feb 2020, 6:38 pm

Hi this manual is readable as to numbering on coil its the mw and topband coils that are burnt. the cap to chassis is s/c so likley live chassis to ground via the 2 coils as r1 is also crispy/missing. I hope no one was hurt. This seems to have been used in the uk as on the tuning dial is has Home Light AFN and Hilversham marked on dial it is still 110volt in but had a 13a plug fitted. The rx had an oc heater in the rectifier tube the pilot lamp also oc as was the 330ohm across the pilot lamp not forgetting the exploded smoothing block. purchased from that bid site saying "it lights up" yes i bet it did. With the readable manual i am going to remove the coil and rewind Mick

FrankB · 22nd Feb 2020, 3:38 am

Please keep in mind the Hallicrafters S38 series is also, sadly, prone to silver mica disease and poor insulation on the IFT's.
(Actually, most of the Hallicrafters are prone to this. I had a large collection of them of assorted models and offed the whole pile, as I was tired of repairing the IFT's.)
SMD caps do work good for replacing the silver mica caps in the IFT's.

regenfreak · 22nd Feb 2020, 2:25 pm

Quote:

Originally Posted by FrankB

Please keep in mind the Hallicrafters S38 series is also, sadly, prone to silver mica disease and poor insulation on the IFT's.
(Actually, most of the Hallicrafters are prone to this. I had a large collection of them of assorted models and offed the whole pile, as I was tired of repairing the IFT's.)
SMD caps do work good for replacing the silver mica caps in the IFT's.

I have been resisting the urge to import the S38 from the USA. The shipping and import taxes cost more than the receiver itself. I purchased a few AA5 and AA6 domestic sets from the USA, luckily the smaller IFs are all free from SMD.Touch wood.

I would not enjoy replacing the caps in IFs either.

Dave757 · 22nd Feb 2020, 6:20 pm

Hi,

Yes, you're right about the costs. There's an S38c in the States on eBay at the moment, and the total cost is around £158 to
include import duty and shipping. The current price of the set itself - £54.01!

Not much of a set as I remember, but you might come across one in the
UK cheaply.

Kind regards
Dave

17th Feb 2020, 12:12 pm	#1
mickm3for Heptode Join Date: May 2015 Location: Chatham, Kent, UK. Posts: 963	Hallicrafters S38 Hi i have this s38 it now works But the range 1 and 2 aerial coils are burnt they are black and open circuit do i dismantle (not an easy job ) and rewind or use cap coupling to top of tuned circuit , using this it seems rather deaf. What would you do please? Mick Attached Thumbnails Last edited by mickm3for; 17th Feb 2020 at 12:17 pm.

17th Feb 2020, 1:57 pm	#2
HamishBoxer Dekatron Join Date: Aug 2007 Location: W.Butterwick, near Doncaster UK. Posts: 8,932	Re: Hallicrafters S38 Rewinding would of course be best.Wonder what caused the burn up.Just a thought ,could you fit replacements anywhere else? __________________ G8JET BVWS Archivist and Member V.M.A.R.S

17th Feb 2020, 2:40 pm	#3
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 13,996	Re: Hallicrafters S38 If you can find a "full" manual for the receiver, it may include details of the coil inductances, which would make rewinding a bit easier. As to why they've 'cooked', is it a live-chassis AC/DC receiver? If so, I wonder if it could have been wired with the chassis 'live', then the aerial was earthed and the coils got to pass mains-current? Quite a few US radios tried to get round the 'live chassis' thing by using a negative-rail bus-bar which was not connected to the chassis except via a small RF-bypass capacitor (1000pF or so) and a parallel receiver (100K?) to act as a static-bleed. If the bus-bar is inadvertently shorted to the chassis, or the RF-bypass capacitor goes short-circuit, it can lead to the antenna-coil being zapped,.

17th Feb 2020, 5:57 pm	#4
g4aaw pete Heptode Join Date: Jan 2008 Location: Birchington Kent, UK. Posts: 596	Re: Hallicrafters S38 The manual here for the S38B seems to have coil info http://www.radiosurplus.it/pdf/S-38B.pdf __________________ Regards Pete

17th Feb 2020, 6:38 pm	#5
mickm3for Heptode Join Date: May 2015 Location: Chatham, Kent, UK. Posts: 963	Re: Hallicrafters S38 Hi this manual is readable as to numbering on coil its the mw and topband coils that are burnt. the cap to chassis is s/c so likley live chassis to ground via the 2 coils as r1 is also crispy/missing. I hope no one was hurt. This seems to have been used in the uk as on the tuning dial is has Home Light AFN and Hilversham marked on dial it is still 110volt in but had a 13a plug fitted. The rx had an oc heater in the rectifier tube the pilot lamp also oc as was the 330ohm across the pilot lamp not forgetting the exploded smoothing block. purchased from that bid site saying "it lights up" yes i bet it did. With the readable manual i am going to remove the coil and rewind Mick Last edited by mickm3for; 17th Feb 2020 at 6:40 pm. Reason: missed part out

22nd Feb 2020, 3:38 am	#6
FrankB Heptode Join Date: Oct 2005 Location: Olympia, Washington, USA. Posts: 664	Re: Hallicrafters S38 Please keep in mind the Hallicrafters S38 series is also, sadly, prone to silver mica disease and poor insulation on the IFT's. (Actually, most of the Hallicrafters are prone to this. I had a large collection of them of assorted models and offed the whole pile, as I was tired of repairing the IFT's.) SMD caps do work good for replacing the silver mica caps in the IFT's.

22nd Feb 2020, 6:20 pm	#8
Dave757 Heptode Join Date: Apr 2009 Location: Scratby, Norfolk, UK. Posts: 650	Re: Hallicrafters S38 Hi, Yes, you're right about the costs. There's an S38c in the States on eBay at the moment, and the total cost is around £158 to include import duty and shipping. The current price of the set itself - £54.01! Not much of a set as I remember, but you might come across one in the UK cheaply. Kind regards Dave