VHF-FM (and other) DX: Todd Emslie - UK Vintage Radio Repair and Restoration Discussion Forum

Nymrod121 · 12th Aug 2020, 8:30 pm

Todd Emslie (Australia) has been in touch with me regarding VHF-FM DX etc. He makes reference to several Practical Wireless articles & is happy for me to post edited highlights here:

"Thanks Guy for the two interesting FM Yagi, and workshop shed photos.

It appears that Simon David ceased writing the VHF/FM DX column after the September, 1974 PW issue. The editor notified this in the October, 1974 issue:

https://worldradiohistory.com/UK/Pra...PW-1974-10.pdf

This was [Simon] David's last column in September, 1974:

https://worldradiohistory.com/hd2/ID...-Page-0076.pdf

The Korner 9.2 Yagi is particularly noteworthy for its high average 31 dB front-to-back ratio towards the low end of the FM band. This is of course where most of the double-hop sporadic E receptions occur.

One current drawback is the inordinately slow air mail times due to restricted international air traffic. This has delayed my purchase of the 9.2 Yagi. Until international post times return back to normal, I will defer overseas purchases.

Yes, go ahead and reproduce the full contents of my emails on the vintage radio forum. In order to reduce possible spam, it is best to not put my email address on the forum.

The Practical Wireless issues can be saved as individual pages, or full issues in PDF. They go back to at least the mid 1960s.

Regards,

Todd

On Wednesday, August 12, 2020, 04:40:20 PM GMT+10, [Guy] wrote:

Hello Todd,

Thank you for your email - and with such fascinating links! Such is the power of the internet.

<text redacted to comply with VRF rules>

The recently available Band II antenna (German) looks tempting both in terms of performance and price.

I still have one of my two original 'Fuba Exa Stereo 8' antennas in service (see pics) but due to planning/aesthetic constraints it does not have much height-gain advantage and is only rotatable by means of the Armstrong method (i.e. going up a ladder on to my garage roof and lifting/manhandling the concrete slab to which its mounting pole is fixed). It is currently aligned due South and in conjunction with a "Woolworths" FM/DAB radio in my workshop tuned to 'Sam-FM' on 106.00MHz from the Chillerton Down 1kW transmitter on the Isle of Wight, I use this system as an everyday check of propagation conditions.

I wonder if I might post a suitably-redacted version of your email on vintage-radio.net ?

Kindest regards,

Guy

On Wed, 12 Aug 2020, 06:53 Todd Emslie, <email address redacted at his request> wrote:

Hello Guy,

Via a Google keyword search, I was pleased to find that some individuals had gone to considerable effort in scanning TELEVISION magazine, and Practical Television issues going back to the early 1960s. These were of special interest for my DX TV and FM hobbies. I downloaded these scans into a dedicated folder on my PC.

A later Google search revealed Practical Wireless scanned issues going back to the early 1960s. These are also of special interest to MW DXers, in particular the articles by Ken Brownless (then-MW DX Circle chief editor), and Charles Molloy (one of the UK's leading MW DXers who later became chief editor of the MW DX Circle in 1973).

The MW Column by Charles Molloy is one of the most comprehensive archive sources for what UK MW DXers were hearing in the 1960s and 1970s. The MW logs compared to now are spectacular. Arguably, this was mainly due to enhanced propagation conditions back in the day. But just as likely is the increased number of high power stations on air. The receiving gear used in the 1960s was not better than what we use now. Hence the equipment was not a standout factor for their success.

The indoor 40 inch side length wood frame square box loop was mainly used by the top UK MW DXers in the 1960s. The following 1966 PW article shows construction details for a 40 inch side length square box loop:

https://worldradiohistory.com/hd2/ID...-Page-0067.pdf

https://worldradiohistory.com/hd2/ID...-Page-0068.pdf

In the April, 1970 issue, Charles Molloy wrote a general equipment and propagation article on MW DX. This article was soon also published in Electronics Australia.

https://worldradiohistory.com/hd2/ID...-Page-0055.pdf

https://worldradiohistory.com/hd2/ID...-Page-0056.pdf

The receivers most commonly used are detailed in the following link. Note that Charles Molloy used Marconi CR100, and WWII ex-military BC314 tube receivers.

https://worldradiohistory.com/hd2/ID...-Page-0058.pdf

The tube receivers used in the 1960s were highly resistant to spurious signal overload. But a 1960s state-of-the-art transistor communications receiver (very few were available), would have likely performed satisfactorily with minimal or no spurious signals provided it was used with a high Q passive 40 inch box loop. Keep in mind that virtually all serious medium wave DXers in 1969 used tube receivers. The few that didn't used solid state portables.

A Sangean PR-D3, D5, D15, or Crane / Sangean CC 2E solid state AM portable would have amazed 1969 MW DXers. The superior sound quality would have been the first standout improvement over their muffled audio tube receivers. Tuning precision down to 1 KHz digital readout would have been enough for many of them to discard the tube receivers. These high-end modern Sangean and Crane physically larger size portables do not overload when used with a high Q passive loop.

Regards,

Todd

https://worldradiohistory.com/hd2/ID...-Page-0071.pdf

https://worldradiohistory.com/hd2/ID...-Page-0080.pdf

https://worldradiohistory.com/hd2/ID...-Page-0076.pdf

PS: A new commercially available FM DX antenna from Germany:

https://www.antennenland.net/3H-FM-9M19

http://ham-radio.com/k6sti/korn92.htm

Hope this is of interest (and Mods: please do relocate if deemed appropriate)

Best wishes
Guy

G6Tanuki · 12th Aug 2020, 8:40 pm

That's a wonderful scavenge through the archives!!

My FM-DX stuff only extended to a FUBA UKA8 on a rotator, a set of 'shorted-line' coax-stub filters to notch-out the annoying BBC National stations below 95MHz [you could get 30dB attenuation] and a 40673 MOSFET amplifier.

FM-DX can still be fun!

12th Aug 2020, 9:16 pm

Any DXing (or even any radio from a bit outside its supposed area) is fun, I can't understand the "well I can get anything on the internet" full stop argument. One of my favorites is the RSL (restricted service license) 1W MW stations, yup a whole watt. Adding to the fun is taking a motorcycle ride to find the station, you get the odd look though!

12th Aug 2020, 8:30 pm	#1
Nymrod121 Nonode Join Date: Apr 2012 Location: Worcestershire, UK. Posts: 2,052	VHF-FM (and other) DX: Todd Emslie Todd Emslie (Australia) has been in touch with me regarding VHF-FM DX etc. He makes reference to several Practical Wireless articles & is happy for me to post edited highlights here: "Thanks Guy for the two interesting FM Yagi, and workshop shed photos. It appears that Simon David ceased writing the VHF/FM DX column after the September, 1974 PW issue. The editor notified this in the October, 1974 issue: https://worldradiohistory.com/UK/Pra...PW-1974-10.pdf This was [Simon] David's last column in September, 1974: https://worldradiohistory.com/hd2/ID...-Page-0076.pdf The Korner 9.2 Yagi is particularly noteworthy for its high average 31 dB front-to-back ratio towards the low end of the FM band. This is of course where most of the double-hop sporadic E receptions occur. One current drawback is the inordinately slow air mail times due to restricted international air traffic. This has delayed my purchase of the 9.2 Yagi. Until international post times return back to normal, I will defer overseas purchases. Yes, go ahead and reproduce the full contents of my emails on the vintage radio forum. In order to reduce possible spam, it is best to not put my email address on the forum. The Practical Wireless issues can be saved as individual pages, or full issues in PDF. They go back to at least the mid 1960s. Regards, Todd On Wednesday, August 12, 2020, 04:40:20 PM GMT+10, [Guy] wrote: Hello Todd, Thank you for your email - and with such fascinating links! Such is the power of the internet. <text redacted to comply with VRF rules> The recently available Band II antenna (German) looks tempting both in terms of performance and price. I still have one of my two original 'Fuba Exa Stereo 8' antennas in service (see pics) but due to planning/aesthetic constraints it does not have much height-gain advantage and is only rotatable by means of the Armstrong method (i.e. going up a ladder on to my garage roof and lifting/manhandling the concrete slab to which its mounting pole is fixed). It is currently aligned due South and in conjunction with a "Woolworths" FM/DAB radio in my workshop tuned to 'Sam-FM' on 106.00MHz from the Chillerton Down 1kW transmitter on the Isle of Wight, I use this system as an everyday check of propagation conditions. I wonder if I might post a suitably-redacted version of your email on vintage-radio.net ? Kindest regards, Guy On Wed, 12 Aug 2020, 06:53 Todd Emslie, <email address redacted at his request> wrote: Hello Guy, Via a Google keyword search, I was pleased to find that some individuals had gone to considerable effort in scanning TELEVISION magazine, and Practical Television issues going back to the early 1960s. These were of special interest for my DX TV and FM hobbies. I downloaded these scans into a dedicated folder on my PC. A later Google search revealed Practical Wireless scanned issues going back to the early 1960s. These are also of special interest to MW DXers, in particular the articles by Ken Brownless (then-MW DX Circle chief editor), and Charles Molloy (one of the UK's leading MW DXers who later became chief editor of the MW DX Circle in 1973). The MW Column by Charles Molloy is one of the most comprehensive archive sources for what UK MW DXers were hearing in the 1960s and 1970s. The MW logs compared to now are spectacular. Arguably, this was mainly due to enhanced propagation conditions back in the day. But just as likely is the increased number of high power stations on air. The receiving gear used in the 1960s was not better than what we use now. Hence the equipment was not a standout factor for their success. The indoor 40 inch side length wood frame square box loop was mainly used by the top UK MW DXers in the 1960s. The following 1966 PW article shows construction details for a 40 inch side length square box loop: https://worldradiohistory.com/hd2/ID...-Page-0067.pdf https://worldradiohistory.com/hd2/ID...-Page-0068.pdf In the April, 1970 issue, Charles Molloy wrote a general equipment and propagation article on MW DX. This article was soon also published in Electronics Australia. https://worldradiohistory.com/hd2/ID...-Page-0055.pdf https://worldradiohistory.com/hd2/ID...-Page-0056.pdf The receivers most commonly used are detailed in the following link. Note that Charles Molloy used Marconi CR100, and WWII ex-military BC314 tube receivers. https://worldradiohistory.com/hd2/ID...-Page-0058.pdf The tube receivers used in the 1960s were highly resistant to spurious signal overload. But a 1960s state-of-the-art transistor communications receiver (very few were available), would have likely performed satisfactorily with minimal or no spurious signals provided it was used with a high Q passive 40 inch box loop. Keep in mind that virtually all serious medium wave DXers in 1969 used tube receivers. The few that didn't used solid state portables. A Sangean PR-D3, D5, D15, or Crane / Sangean CC 2E solid state AM portable would have amazed 1969 MW DXers. The superior sound quality would have been the first standout improvement over their muffled audio tube receivers. Tuning precision down to 1 KHz digital readout would have been enough for many of them to discard the tube receivers. These high-end modern Sangean and Crane physically larger size portables do not overload when used with a high Q passive loop. Regards, Todd https://worldradiohistory.com/hd2/ID...-Page-0071.pdf https://worldradiohistory.com/hd2/ID...-Page-0080.pdf https://worldradiohistory.com/hd2/ID...-Page-0076.pdf PS: A new commercially available FM DX antenna from Germany: https://www.antennenland.net/3H-FM-9M19 http://ham-radio.com/k6sti/korn92.htm Hope this is of interest (and Mods: please do relocate if deemed appropriate) Best wishes Guy __________________ "What a depressingly stupid machine." [Marvin: HHGTTG]

12th Aug 2020, 8:40 pm	#2
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 14,005	Re: VHF-FM (and other) DX: Todd Emslie That's a wonderful scavenge through the archives!! My FM-DX stuff only extended to a FUBA UKA8 on a rotator, a set of 'shorted-line' coax-stub filters to notch-out the annoying BBC National stations below 95MHz [you could get 30dB attenuation] and a 40673 MOSFET amplifier. FM-DX can still be fun!

12th Aug 2020, 9:16 pm	#3
Guest Guest Posts: n/a	Re: VHF-FM (and other) DX: Todd Emslie Any DXing (or even any radio from a bit outside its supposed area) is fun, I can't understand the "well I can get anything on the internet" full stop argument. One of my favorites is the RSL (restricted service license) 1W MW stations, yup a whole watt. Adding to the fun is taking a motorcycle ride to find the station, you get the odd look though!