Vintage Tuners and the Aerial you use ?

[Spectral Morn]

Hi Guys


As some of you are aware I am/have starting my tuner mega review. Very early days yet, but the combatants are now all in, and an interesting discovery has made about my choice of aerial, which makes things a wee bit more complicated than I thought.

General wisdom would suggest a nice big multi element aerial, mounted outside or in the loft is the ideal. These would all be of the 75 ohm type, using co-ax cable and an F Type or Belling Lee connector for hook up to the tuner. Well it seems that if you are using a late 60s or early to mid 70s tuner that might not be the best way.

Many of these tuners were actually designed to work just as well or better with a 300 Ohm cable aerial (the type we usually call Wet String). So if you use a tuner of this sort of vintage (with good sensitivity and selectivity), and live close to the transmitter, then I think you owe it to yourself to try it out. A 300 Ohm aerial will only cost you a few quid and the results may shock you.

This came to light after doing some research about a tuner in for test, a classic Sony. It like many of its early competitors prefer a 300 Ohm aerial, over a 75 Ohm. You can imagine my shock when the signal strength VU meter indicated the same levels of strength, as I was getting from the 5 element Yagi in the loft...and this from what I would view as a piece of rubbish wire. Oh yes sound quality...better too.

I will now be trying both types of aerials during this test period with all the early tuners....300 Ohm aerial now installed, in the downstairs listening room where the listening tests will be done.

So give it a try with your own tuner and let me know what you think of the results. This is not just about signal strength, but sound quality.


Regards D S D L

[The Grand Wazoo]

Well, they put both connectors on there for a reason, Neil & those Japanese guys knew their way round a tuner in those days! I swear some of those tuners could pick up a good signal with a wet fart!!
Somehow, though they never managed to pass on their wisdom.

Back when I was buying tuners like they were going out of fashion I used to try both & had several aerial options available to me. I made a few 300 Ohm types too, much better than those you buy now.
I usually found that the 75 ohm type was more stable & less prone to variations caused by weather conditions (I assumed).

[Spectral Morn]

Well, they put both connectors on there for a reason, Neil & those Japanese guys knew their way round a tuner in those days! I swear some of those tuners could pick up a good signal with a wet fart!!
Somehow, though they never managed to pass on their wisdom.

Back when I was buying tuners like they were going out of fashion I used to try both & had several aerial options available to me. I made a few 300 Ohm types too, much better than those you buy now.
I usually found that the 75 ohm type was more stable & less prone to variations caused by weather conditions (I assumed).

What did you use for your 300 Ohm Aerial Chris ?

I am learning so much during this project, but fully realise I have much still to discover.


Regards D S D L

[DSJR]

Neil, you're quite correct. Bring back to measurement led HiFi Choice tuner group trests. All this was thoroughly gone into and sound quality was referred to master-tape into an FM modulator and then back through the tuner. I remember some Yamaha tuners and receivers where the replacement models didn't work properly on the 75 Ohm connections, yet the 300 Ohm ones were fine. The previous models were fine on both...

Amazing how some tuners sssplitched and sssplatched their way along in sound quality, although the better ones are the mostly the ones favoured by the subjectivists still..

[The Grand Wazoo]

Neil,
I used to use the ladder type 300 ohm cable which is like your wet string aerial, but has slotted holes between the conductors this seemed to be better quality than the usual type. Mine had black insulation – like this:
http://www.hamradiosupplies.co.uk/co...r/prod_38.html
Not where I bought it from at the time but I used to get it from ham radio type shops like this one.
The beauty of building your own is that you can go big, making it any size you want (or can afford, or can accommodate) and you can make it the perfect size for your favoured station.
This is a good but basic article – it gives you the maths for finding the ideal length.
http://www.cyberpoet.net/writes/web/infwiz/spant.html

[Spectral Morn]

Neil,
I used to use the ladder type 300 ohm cable which is like your wet string aerial, but has slotted holes between the conductors this seemed to be better quality than the usual type. Mine had black insulation – like this:
http://www.hamradiosupplies.co.uk/co...r/prod_38.html
Not where I bought it from at the time but I used to get it from ham radio type shops like this one.
The beauty of building your own is that you can go big, making it any size you want (or can afford, or can accommodate) and you can make it the perfect size for your favoured station.
This is a good but basic article – it gives you the maths for finding the ideal length.
http://www.cyberpoet.net/writes/web/infwiz/spant.html

Thanks Chris

I will look into it.


Regards D S D L

[Mike Reed]

Excuse my higgorance here, but having had some (but not much) experience and frustration in the past with 300 ohm screw terminals (usually) and 75 ohm coax, I'd like to ask:

Didn't a thing called a 'balun' convert 300 to 75 ohm (I don't remember it the other way round)?

Wasn't the gradual take-over of 75ohm coax and directional arrays because of the far better capture properties afforded over the 'piece of string'? This latter only worked in strong signal areas and did nothing for ghosting, birdies and intrusive unwanted signals.

Neil, you talk about a 'Yagi'. I thought this was a stacked arrangement of collectors more in use for TV reception. As I've only had 4, 6, 8 and 23 element Ron Smith aerials in my life, I can't imaging your array.

However, pre 1965 stereo tuners may have had circuitry that definitely favoured 300 ohms; someone with a technical bent may be better able to assess this possibility.

[Spectral Morn]

Excuse my higgorance here, but having had some (but not much) experience and frustration in the past with 300 ohm screw terminals (usually) and 75 ohm coax, I'd like to ask:

Didn't a thing called a 'balun' convert 300 to 75 ohm (I don't remember it the other way round)?

Wasn't the gradual take-over of 75ohm coax and directional arrays because of the far better capture properties afforded over the 'piece of string'? This latter only worked in strong signal areas and did nothing for ghosting, birdies and intrusive unwanted signals.

Neil, you talk about a 'Yagi'. I thought this was a stacked arrangement of collectors more in use for TV reception. As I've only had 4, 6, 8 and 23 element Ron Smith aerials in my life, I can't imaging your array.

However, pre 1965 stereo tuners may have had circuitry that definitely favoured 300 ohms; someone with a technical bent may be better able to assess this possibility.

Hi Mike

Yes you are correct a Balun will convert a 300 Ohm ribbon aerial to a 75 Ohm connection, you are also right in saying that Tuner aerial designs became more focussed on 75 Ohm connection because of exactly the reasons you state. However pre 1974 tuners (possibly later too) were, or so it seems designed to favour the 300 Ohm ribbon aerial and thus give better results and sound.

As a prelude to my tuner comparison review I have been gathering up as much info as I can, and it seems from what I have read so far that this quirk of design seemed to go into the 70's longer than I might have thought. A number of classic highly regarded Japanese tuners, will or so it is written sound better on a 300 Ohm aerial. I hope to clarify that during my review.

One of the main reason for this project is to give a UK slant to what for the most part is American or European points of view. I am not challenging what has been written elsewhere, as such, but I want to find out for myself, and share my results with a UK point of view.

One other area of contested wisdom, is that the Leak Trough-Line is one of the best tuners available. Now I am a fan of this tuner, but consistently many claim its not that good...I aim to see if thats true or not.

The aerial I use was described to me as being a Yagi design, though not a Yagi itself...photos of it are in SOG "Thats a big one"


Regards D S D L

[Rare Bird]

Am i missing something here, is it gospel that FM boadcast is history within 5 years?

I don't think i could be bothered with all this for such short term & why the hell people are paying a kings ranson for say vintage tuners is beyond me!

Sorry for coming across as a bummer

[Spectral Morn]

Am i missing something here, is it gospel that FM boadcast is history within 5 years?

I don't think i could be bothered with all this for such short term & why the hell people are paying a kings ranson for say vintage tuners is beyond me!

Sorry for coming across as a bummer

Hi Andre

No not at all. However recent events may lead to FM going on longer than 5 years (see Hi-Fi World last month). A number of radio broadcasters are rebelling against the BBC led switch off.

Even if FM is switched off in 5 years (very doubtful) I will continue to use FM till then. 5 years is long enough time, to make an exercise like this still imho worthwhile.


Regards D S D L