Ofcom report on domestic aerials

Java Jive wrote:

Braunton
Analog: Braunton 39 45 49 42 2W B V ...
Digital:Braunton ... BH 39 45 49 42

Old BBC and ITC printed matter says it was H pol analogue. Mb21 pictures show
HP Tx too:-

http://tx.mb21.co.uk/gallery/braunton.php

Porthleven
Analog: Porthleven 33 26 23 29 1.6W A V ...
Digital:Porthleven ... AH 33 26 23 29

Old BBC and ITC printed matter also says it was V pol analogue. Mb21 pictures
show HP Tx , (and Adrian confirmed that discrepancy) and it's acknowledged by
Mb21.

http://tx.mb21.co.uk/gallery/porthleven.php

Porthtowan
Analog: Porthtowan 21 27 24 31 8W A H ...
Digital:Porthtowan ... AV 21 27 24 31

Old BBC and ITC printed matter also says it was V pol analogue. Mb21 pictures
show VP Tx.

http://tx.mb21.co.uk/gallery/porthtowan.php


Widecombe In The Moor
Analog: Widecombe 40 46 43 50 10W B V ...
Digital:Widecombe ... BH 40 46 43 50

Old BBC and ITC printed matter also says it was V pol analogue. Mb21 pictures
show HP Tx.

http://tx.mb21.co.uk/gallery/widecombe-in-the-moor.php

As you say the level of accuracy, surprisingly even on 'pre web' Beeb, and
ITC/IBA literature leaves a great deal to be desired.

I doubt any relay stations have physically changed polz, it's all down to
typos I suspect.


--
Mark
Please replace invalid and invalid with gmx and net to reply.

www.paras.org.uk

J G Miller wrote:
On Wed, 13 Jan 2010 20:30:31 +0000, Mark Carver wrote:

If anything the post DSO transmissions are too powerful.
c.f. Moel-y- Parc's overlap into Granadaland.

But Moel-y-Parc has always overlapped into Granadaland and Winter Hill
into Gogledd Cymru.

Indeed it has. It might have been appropriate if the DSO re-engineering at MyP
had included a provision to reduce this overlap, perhaps using beam tilt
techniques ?

You would think that people would be glad of the extra choice and the
exposure to different news and culture from across the territorial
frontier, but all many English people do is complain and whine about
having the minor inconvenience of having to re-order the stations on
their digital converter boxes.

Such action is way beyond the ability of millions.

--
Mark
Please replace invalid and invalid with gmx and net to reply.

www.paras.org.uk

On 14/01/2010 16:01, Mark Carver wrote:
Java Jive wrote:

Braunton
Analog: Braunton 39 45 49 42 2W B V ...
Digital:Braunton ... BH 39 45 49 42

Old BBC and ITC printed matter says it was H pol analogue. Mb21 pictures
show HP Tx too:-

http://tx.mb21.co.uk/gallery/braunton.php

Porthleven
Analog: Porthleven 33 26 23 29 1.6W A V ...
Digital:Porthleven ... AH 33 26 23 29

Old BBC and ITC printed matter also says it was V pol analogue. Mb21
pictures show HP Tx , (and Adrian confirmed that discrepancy) and it's
acknowledged by Mb21.

http://tx.mb21.co.uk/gallery/porthleven.php

Porthtowan
Analog: Porthtowan 21 27 24 31 8W A H ...
Digital:Porthtowan ... AV 21 27 24 31

Old BBC and ITC printed matter also says it was V pol analogue. Mb21
pictures show VP Tx.

http://tx.mb21.co.uk/gallery/porthtowan.php


Widecombe In The Moor
Analog: Widecombe 40 46 43 50 10W B V ...
Digital:Widecombe ... BH 40 46 43 50

Old BBC and ITC printed matter also says it was V pol analogue. Mb21
pictures show HP Tx.

http://tx.mb21.co.uk/gallery/widecombe-in-the-moor.php

As you say the level of accuracy, surprisingly even on 'pre web' Beeb,
and ITC/IBA literature leaves a great deal to be desired.

I doubt any relay stations have physically changed polz, it's all down
to typos I suspect.


My old BBC "yellow book" gives Braunton as H, Porthleven as H and
Porthtowan as V. Too old for Widecombe, though I remember doing the pre
site test survey.

Phil

Java Jive wrote:
Here the full list of what I've found, excluding the resolutions
already achieved, and also excluding those arising from mis-applied
aerial nomenclature. My thoughts/conclusions are in CAPS:

Using old BBC and IBA guides, these are the correct ones, assuming my guides
are, which they'll most likely to be


Ambergate 22 28 25 32 37W A V

Barnstaple KV 40 46 43 30
However now post DSO, now 43, 46, 50 and Group B (though of course K will
still work)

Bassenthwaite BV 52 45 49 42
BV and still BV post DSO

Caldbeck WH 30 34 28 32 56
Calbeck now Post DSO, all channels in Group A and H

Cambret Hill BH 44 51 41 47 37
Cambret now post DSO, 44, 41, 47 Still BH

No info - I had presumed it was a transmitter new with DSO!
Chaigley AV 21 27 24 31

Which parent station ? Can't be a post DSO Tx, it's 4 channel, and using Ch
31 (a non DSO alloction)

Chepstow 21 27 24 31 3.1W A V
Chepstow AV 21 27 24 31
NO REAL ERROR - CHANNEL 4/S4C NAMES

Chepstow is a BBC Wenvoe (Wales) and IBA Mendip (Bristol) relay. Carries C4
not S4C, after DSO will be Wenvoe relay for all three muxes

Cilycwm 21 27 24 31 7W A V
Cilycwm AV 21 27 31 24
CHANNEL ORDER
Why worry, doesn't affect aerial usage ?

Compton EV 51 44 68 47
However now post DSO, now 41, 44, 47 and Group B (though of course E will
still work)

Croyde BV 51 44 41 47
However now post DSO, now 41, 44, 47 and Group B

Darley Dale 30 48 34 52 16W W V
Darley Dale K/WV 30 48 34 52
Both K and W groups are valid (K covers 21-48)
Post DSO will be 41, 44, 47 Group B but K and W still valid.

Derby 48 30 200W W H
Derby K/WH 48 30
Both K and W groups are valid (K covers 21-48)
Post DSO will be 48, 51, 52 Group B but K and W still valid.

14)
Dunoon 21 24 27 31 2W A V
Dunoon AV 21 27 24 31
CHANNEL ORDER
Why worry, doesn't affect aerial usage ?

Durness 57 63 53 60 7W C/D V


Ferryside 31 23W A V
Ferryside AV 31
Ferryside AV 27
Ferryside was the site of an early DSO experiment, it's been all over the
shop, but pre and post DSO has remained AV. It's also the only post DSO small
relay to carry 4 muxes (rather than the usual three)

17)
Frome 21 27 24 31 10W A V
Frome AV 21 24 27 31
CHANNEL ORDER
Why worry, doesn't affect aerial usage ?


Glyncorrwg BV 39 45 49 42
Now post DSO, 42,45,49 BV

Headingley C/DH 58 64 61 54

Hebden Bridge AV 22 28 25 32


Holmfirth 39 66 56 68 26W C/D V
Holmfirth E/WV 39 66 56 68

BBC and IBA 1989 data shows BBC 1 on 49 (not 39). It must have moved to 39 in
1998 to avoid a clash with Mux D at Emley, thus requiring an aerial group
change from C/D to W (or E). The DVB-T2 mux from Emley starts this March on Ch
39, so there might be another move soon. Post DSO it will be 54, 58, 61 so
back to C/D (though Es and Ws will be OK)


No info - Again I had assumed this was a transmitter new with DSO!
Jurby C/DV 54 64

Jurby (along with Ramsey) was an odd relay, only ever carried BBC 1 and 2 on
54 and 64, no ITV or C4. Post DSO it now carries three muxes on 43,46,50 so
has moved from C/DV to B

Les Touillets 56 48 54 52 2kW C/D H
Les Touillets C/DV 56 48 54 52
SECOND?
http://tx.mb21.co.uk/gallery/les-touillets.php
Presuming that the whitish vertical column at the top is the TV TX, as
that is vertical in shape, presumbalby V, and that agrees with post
DSO.

No Les Touillets is (unsually for a high power relay) HP. Group C/D.
The Ofcom data does indeed say V post DSO. I suspect this is wrong, and it
will remain HP.

No info - Again I had assumed this was a transmitter new with DSO!
Lochgoilhead AD AV 33 26 23 29
SECOND
(Not to be confused with Lochgoilhead. What does AD stand for?)

Lochgoilhead AD must be an active deflector to feed the main Lochgoilhead site.
Parent station Darvel uses 33,26,23,29 too. It may well have viewers of its
own however. I suspect it will remain Group A following Darvel's 22,25,28 post
DSO allocations.

Monksilver 45 48 52 42 15W B V
Monksilver BV 45 48 42 52
CHANNEL ORDER
Why worry, doesn't affect aerial usage ?


Neath Abbey HP E/WH 66 48 42 56
Neath Abbey VP E/WV 66 48 42 56
SECOND

Yes, Neath Abbey carries H and V signals to different parts of its service
area. Now Post DSO it is 48,52,56 and Group CD H and V (E is still OK to use)

No info - Again I had assumed this was a transmitter new with DSO!
Ramsey C/DH 66 68
Like Jurby, only ever carried BBC 1 and 2 on 66 and 68, no ITV or C4. Post DSO
it now carries three muxes on 42,45,49 so has moved from C/DH to BH


Rumster Forest 31 27 24 21 100kW A H

Main station, always been HP and will be still post DSO

Salcombe WV 51 41 44 30
Now post DSO, 41,44, 47 Group B V (W aerials OK still)

St. Brelades 57 67 63 54 8W C/D V

http://tx.mb21.co.uk/gallery/st-brelades.php
Looks to me as though it receives in H (correct for Fremont) and
rebroadcasts in V?

Yes

St Neot 39 45 49 42 3.2W B V
St Neot BV 39 42 49 45
CHANNEL ORDER
Why worry, doesn't affect aerial usage ?

Storeton KV 22 28 25 32 39
Post DSO now English DTT transmissions all in Group A (New Welsh post DSO
transmissions are a different kettle of fish)

Wrexham-Rhos 22 28 32 25 200W A V
Wrexham Rhos K/WV 39 28 32 25

The site has jumbled up its analogue allocations several times over the years,
to allow for DTT transmissions. It started life as a two channel relay
carrying BBC 1 Wales on 39, and S4C on 67. So it was Group E, ended life as a
analogue site carrying the four Welsh channels on 39, 28, 32, 67, plus C4
England on 25. Making it Wideband. Post DSO is now 22,25,28 and A Vert


--
Mark
Please replace invalid and invalid with gmx and net to reply.

www.paras.org.uk

On Thu, 14 Jan 2010 23:26:46 +0000, Java Jive
wrote:

1)
Ambergate 22 28 25 32 37W A V
Ambergate BV 51 44 41 47
COMPLETE MISMATCH. ANYONE ABLE TO HELP?

The first line certainly WAS correct until a few years ago.

If the second line comes from a very recent source it might be due to
a site change, otherwise I would suggest it is wrong.
A complete change like this is not unknown, but quite rare for obvious
reasons.

On Fri, 15 Jan 2010 11:55:45 +0000, Mark Carver
wrote:

No info - I had presumed it was a transmitter new with DSO!
Chaigley AV 21 27 24 31

Which parent station ? Can't be a post DSO Tx, it's 4 channel, and using Ch
31 (a non DSO alloction)

Chaigley
power 8w.
parent Winter Hill

lid wrote:
On Fri, 15 Jan 2010 11:55:45 +0000, Mark Carver
wrote:

No info - I had presumed it was a transmitter new with DSO!
Chaigley AV 21 27 24 31
Which parent station ? Can't be a post DSO Tx, it's 4 channel, and using Ch
31 (a non DSO alloction)

Chaigley
power 8w.
parent Winter Hill

Ah yes, found it. Thank you. Still Grp A Vert, 21, 24, 27.

--
Mark
Please replace invalid and invalid with gmx and net to reply.

www.paras.org.uk

On 15/01/2010 15:40, Java Jive wrote:
Thanks to Nemo, and especially to you, for all the help with this,
Mark. To correct these, I shall devise for the programme a system
similar to the ones already in place to correct the names and NGRs.

There are one or two points remaining, and I've also added some more
comments ...

Cilycwm AV 21 27 31 24
CHANNEL ORDER
Why worry, doesn't affect aerial usage ?

No, it won't, and therefore it's not critically important, but as the
data will be displayed in full in the calculator, as far as possible I
would like to avoid negative impressions created by any of it being
wrong, and therefore if possible would like to get the channel orders
correct as well.

Understood. I've left the likely correct one quoted above, and likewise below
the the other stations.

Both K and W groups are valid (K covers 21-48)
Post DSO will be 48, 51, 52 Group B but K and W still valid.

But AIUI, K being the narrower banded alternative is preferable for
performance reasons, so that's what I'll use, unless anyone tells me
different.

No, that's right.

Dunoon 21 24 27 31 2W A V
Dunoon AV 21 27 24 31
CHANNEL ORDER

Don't know. I assume it's in Argyll, that would make it a Black Hill or Darvel
relay, but I can find no details. Must have been one of the very last analogue
relays, circa 1998 ?

Frome 21 27 24 31 10W A V
CHANNEL ORDER

BBC and IBA 1989 data shows BBC 1 on 49 (not 39). It must have moved to 39 in
1998 to avoid a clash with Mux D at Emley, thus requiring an aerial group
change from C/D to W (or E). The DVB-T2 mux from Emley starts this March on Ch
39, so there might be another move soon.

Oh gawd! If DVB-T2 is going to start moving all the existing analogue
channels around again, there's no hope! Given Ofcom's analogue data
is already apparently some years out of date, how the devil can an
ordinary member of the public like myself hope to keep up with these
things?

There's probably going to be more tweaks such as this as DSO progresses
between now and 2013. In the same part of the world, Sheffield (aka Crosspool)
Mux 1 moves this March from Ch 39 to 63, so that Emley can transmit its
interim DVB-T2 service.

Jurby (along with Ramsey) was an odd relay, only ever carried BBC 1 and 2 on
54 and 64, no ITV or C4. Post DSO it now carries three muxes on 43,46,50 so
has moved from C/DV to B

And is now a relay of Douglas.

As an aside, I can't understand why the Isle of Man is not put in its
own region like the Channel Islands. Since it's a tax haven, I can't
think they are much interested in mainland-oriented regional news and
mainland-oriented advertisements for furniture sales!

Well, ITV wise it was always part of Border TV's region, probably to make that
franchise economically viable. In fact Border struggled and in 1982 the IBA
added the Kendal, Windermere, and Coniston relays in the Lake District that
were until then Granada's. Now Border is part of ITV Ltd, and has been more or
less assimilated into Tyne Tees, it made sense for the IOM to switch to
Granadaland at DSO. It's a good question though, why the ITA didn't give the
IOM the same autonomy as the Channel Is ?

No Les Touillets is (unsually for a high power relay) HP. Group C/D.
The Ofcom data does indeed say V post DSO. I suspect this is wrong, and it
will remain HP.

Anyway you can suggest of finding out for sure? I've mailed Ofcom
already about 3 or 4 issues arising out of DVB-T2, and I was already
awaiting a reply to a mail sent pre-Christmas concerning 50(!) other
problems, so I'd rather avoid troubling them again at least until I've
had a reply to the big first one!

It would cause havoc on Guernsey, as the majority of the island use the
transmitter. If it does change pol I'd be amazed, but who knows given the
proximity to France. It's due to switch on Nov 17th this year, so I'd expect
updated info from Ofcom/DUK soon.

Ah, AD = Active Deflector (which does what exactly? But don't worry
too much about answering that ...).

It's a relay that transmits its output on the same frequency as its input.

Further reading:-

http://tx.mb21.co.uk/gallery/bethesda.php

Google sat photos aren't too hot
in that region, so I'm also unsure of exactly where Lochgoilhead and L
AD are. This is what I wrote about them in my big Christmas present
to Ofcom:

I'll let them answer that one !

Monksilver 45 48 52 42 15W B V
CHANNEL ORDER


St Neot BV 39 42 49 45
CHANNEL ORDER

Thanks again for all your help, past and present, Mark.

No worries, it's a useful exercise and cross check for me, because I help
compile this data for publication in the annual 'TV Viewers Guide'

--
Mark
Please replace invalid and invalid with gmx and net to reply.

www.paras.org.uk

On Fri, 15 Jan 2010 16:29:12 +0000, Mark Carver
wrote:

On 15/01/2010 15:40, Java Jive wrote:
Thanks to Nemo, and especially to you, for all the help with this,
Mark. To correct these, I shall devise for the programme a system
similar to the ones already in place to correct the names and NGRs.

There are one or two points remaining, and I've also added some more
comments ...

Cilycwm AV 21 27 31 24
CHANNEL ORDER
Why worry, doesn't affect aerial usage ?

No, it won't, and therefore it's not critically important, but as the
data will be displayed in full in the calculator, as far as possible I
would like to avoid negative impressions created by any of it being
wrong, and therefore if possible would like to get the channel orders
correct as well.

Understood. I've left the likely correct one quoted above, and likewise below
the the other stations.

Both K and W groups are valid (K covers 21-48)
Post DSO will be 48, 51, 52 Group B but K and W still valid.

But AIUI, K being the narrower banded alternative is preferable for
performance reasons, so that's what I'll use, unless anyone tells me
different.

No, that's right.

Dunoon 21 24 27 31 2W A V
Dunoon AV 21 27 24 31
CHANNEL ORDER

Don't know. I assume it's in Argyll, that would make it a Black Hill or Darvel
relay, but I can find no details. Must have been one of the very last analogue
relays, circa 1998 ?

Frome 21 27 24 31 10W A V
CHANNEL ORDER

BBC and IBA 1989 data shows BBC 1 on 49 (not 39). It must have moved to 39 in
1998 to avoid a clash with Mux D at Emley, thus requiring an aerial group
change from C/D to W (or E). The DVB-T2 mux from Emley starts this March on Ch
39, so there might be another move soon.

Oh gawd! If DVB-T2 is going to start moving all the existing analogue
channels around again, there's no hope! Given Ofcom's analogue data
is already apparently some years out of date, how the devil can an
ordinary member of the public like myself hope to keep up with these
things?

There's probably going to be more tweaks such as this as DSO progresses
between now and 2013. In the same part of the world, Sheffield (aka Crosspool)
Mux 1 moves this March from Ch 39 to 63, so that Emley can transmit its
interim DVB-T2 service.

Jurby (along with Ramsey) was an odd relay, only ever carried BBC 1 and 2 on
54 and 64, no ITV or C4. Post DSO it now carries three muxes on 43,46,50 so
has moved from C/DV to B

And is now a relay of Douglas.

As an aside, I can't understand why the Isle of Man is not put in its
own region like the Channel Islands. Since it's a tax haven, I can't
think they are much interested in mainland-oriented regional news and
mainland-oriented advertisements for furniture sales!

Well, ITV wise it was always part of Border TV's region, probably to make that
franchise economically viable. In fact Border struggled and in 1982 the IBA
added the Kendal, Windermere, and Coniston relays in the Lake District that
were until then Granada's. Now Border is part of ITV Ltd, and has been more or
less assimilated into Tyne Tees, it made sense for the IOM to switch to
Granadaland at DSO. It's a good question though, why the ITA didn't give the
IOM the same autonomy as the Channel Is ?

No Les Touillets is (unsually for a high power relay) HP. Group C/D.
The Ofcom data does indeed say V post DSO. I suspect this is wrong, and it
will remain HP.

Anyway you can suggest of finding out for sure? I've mailed Ofcom
already about 3 or 4 issues arising out of DVB-T2, and I was already
awaiting a reply to a mail sent pre-Christmas concerning 50(!) other
problems, so I'd rather avoid troubling them again at least until I've
had a reply to the big first one!

It would cause havoc on Guernsey, as the majority of the island use the
transmitter. If it does change pol I'd be amazed, but who knows given the
proximity to France. It's due to switch on Nov 17th this year, so I'd expect
updated info from Ofcom/DUK soon.

Ah, AD = Active Deflector (which does what exactly? But don't worry
too much about answering that ...).

It's a relay that transmits its output on the same frequency as its input.

Further reading:-

http://tx.mb21.co.uk/gallery/bethesda.php

Google sat photos aren't too hot
in that region, so I'm also unsure of exactly where Lochgoilhead and L
AD are. This is what I wrote about them in my big Christmas present
to Ofcom:

I'll let them answer that one !

Monksilver 45 48 52 42 15W B V
CHANNEL ORDER


St Neot BV 39 42 49 45
CHANNEL ORDER

Thanks again for all your help, past and present, Mark.

No worries, it's a useful exercise and cross check for me, because I help
compile this data for publication in the annual 'TV Viewers Guide'


Dunoon NS 167 771
parent Black Hill


Lochgoilhead has an intermediate active deflector because the active
relay can't get a reliable signal direct.

AD = NS190 977
23 26 29 33

relay = NS 194 978
53 57 60 63
as always, treat the last NGR digits with caution

On Fri, 15 Jan 2010 20:22:31 +0000, Java Jive
wrote:

I've noted all the changes that I'll need to make. As I see it, that
leaves the three points below, which I list again in case anyone else
can help with them. Thanks again.

On Fri, 15 Jan 2010 16:29:12 +0000, Mark Carver
wrote:

Understood. I've left the likely correct one quoted above, and likewise below
the the other stations.

Thanks, details noted.

1)
Dunoon 21 24 27 31 2W A V
Dunoon AV 21 27 24 31
CHANNEL ORDER
Don't know. I assume it's in Argyll, that would make it a Black Hill or Darvel
relay, but I can find no details. Must have been one of the very last analogue
relays, circa 1998 ?

If it helps you or anyone else resolve this, the full details I have
for Dunoon a

Relay of Black Hill
NGR: NS167771
Ht: 82m

The full data lines from the files are (they may wrap of course) ...
Scottish - Analogue - 4 Channels.dat, derived from ...
http://www.ofcom.org.uk/static/recep...ion_id=10.html
Dunoon 21 24 27 31 2W A V 105.78 Arq NS167771 82
Scotland
STV Central - DSO - v2.dat, derived from ...
http://www.ofcom.org.uk/tv/ifi/tech/...al_DSO_v20.pdf
Dunoon NS167771 27 2W 24 2W 21+ 2W AV AV 21 27 24 31

There's probably going to be more tweaks such as this as DSO progresses
between now and 2013. In the same part of the world, Sheffield (aka Crosspool)
Mux 1 moves this March from Ch 39 to 63, so that Emley can transmit its
interim DVB-T2 service.

I'll keep the cyanide tablet handy then ...

2)
No Les Touillets is (unsually for a high power relay) HP. Group C/D.
The Ofcom data does indeed say V post DSO. I suspect this is wrong, and it
will remain HP.

Anyway you can suggest of finding out for sure? I've mailed Ofcom
already about 3 or 4 issues arising out of DVB-T2, and I was already
awaiting a reply to a mail sent pre-Christmas concerning 50(!) other
problems, so I'd rather avoid troubling them again at least until I've
had a reply to the big first one!

It would cause havoc on Guernsey, as the majority of the island use the
transmitter. If it does change pol I'd be amazed, but who knows given the
proximity to France. It's due to switch on Nov 17th this year, so I'd expect
updated info from Ofcom/DUK soon.

Looks like another mail to Ofcom ...

3)
Ah, AD = Active Deflector (which does what exactly? But don't worry
too much about answering that ...).

It's a relay that transmits its output on the same frequency as its input.

Further reading:-

http://tx.mb21.co.uk/gallery/bethesda.php

Thanks.

Google sat photos aren't too hot
in that region, so I'm also unsure of exactly where Lochgoilhead and L
AD are. This is what I wrote about them in my big Christmas present
to Ofcom:

I'll let them answer that one !

Again, if it helps anyone else resolve the NGRs, the full details I
have for Lochgoilhead and Lochgoilhead AD a

Relay of Darvel

Scottish - Analogue - 4 Channels.dat, derived from ...
http://www.ofcom.org.uk/static/recep...ion_id=10.html
Lochgoilhead 57 63 53 60 6W C/D V 152.35 Arq NS194978 48
Scotland
(No info on Lochgoilhead AD)
STV Central - DSO - v2.dat, derived from ...
http://www.ofcom.org.uk/tv/ifi/tech/...al_DSO_v20.pdf
Lochgoilhead NS194978 53 2W 57 2W 60 2W C/DV C/DV 57
63 53 60
Lochgoilhead AD NS190977 22 0.02W 25 0.02W 28 0.02W AV AV
33 26 23 29

MB21:
http://tx.mb21.co.uk/gallery/lochgoilhead.php

Google Satellite Views ...
Lochgoilhead NS194978
http://maps.google.co.uk/maps?q=56.1...-4.908107&z=18
Lochgoilhead AD NS190977
http://maps.google.co.uk/maps?q=56.1...-4.914468&z=18
... from which I conclude that the NGR of one of them, probably
Lochgoilhead, is most likely NS196976, but am less sure of the other.

See my earlier post at 17.54, but also:

Lochgoilhead AD was not intended for domestic reception so there was
no need to publish data.

The original planned ERP's were 8w (relay) and 0.1w (link), but with
such a setup in a remote area it's very possible that they were
tweaked on commissioning. However these are directional transmissions
so the powers are academic unless you have polar diagrams.