Eagle K110 SWR meter - UK Vintage Radio Repair and Restoration Discussion Forum

Alan Stepney · 10th Jul 2009, 3:14 pm

Does anyone have any information on this please.

Brochure, copy of advert, or similar would be ideal.

Top Cap · 10th Jul 2009, 5:31 pm

A picture would help as it might give some idea of its complexity. SWR meters are normally pretty basic but some, like the attached photo, can be a bit more complex. Les

Alan Stepney · 10th Jul 2009, 7:32 pm

I really just need the frequency range, and basics like that.

Herald1360 · 10th Jul 2009, 9:19 pm

What connectors does it have? UHF (SO239)? From the general appearance I should think it's relatively low power and HF only.

Can you tickle it with 10 watts or so into a dummy load to see roughly how the adjustment sensitivity feels?

Alan Stepney · 10th Jul 2009, 9:28 pm

Yes, it is UHF connectors, but a lot of Japanese equipment used them for 2 metres.

The construction looks "VHF", but the power is shown as 16 watts maximum.
Was it for HF, or CB, or for 2 metres?

I dont have an HF Tx to hand, and it wont read off any of the signal generators I have.

Also, it isnt in the 80-81 Eagle catalogue, but someone must know it or have an advert for it somewhere. I hope!

Top Cap · 10th Jul 2009, 10:40 pm

Hi Alan, you may be able to get some idea by its construction. If it contains lines in a screened enclosure (as attached picture) then you may be able to use it up to 200MHz. But if the construction is for example printed circuit lines then it may have been designed for CB radio. The only real way of testing is by using a non inductive 50 Ohm load on the antenna end and feeding it via a suitable instrument to measure its miss-match at higher frequencies. A network analyser would be nice if you know anyone who has access to one.
However I have built some in the past and just used a suitable dummy load on its own, making the assumption that the bridge should give maximum forward but minimum reflected indications on the meter. The acid test then is to reverse everything, placing the load on the transmitter port and injecting a carrier into the antenna port. If the bridge is good, you will see identical results but they will be reversed, i.e. maximum reflected and minimum forward indications. I have checked out some of the meters being offered on the internet but it was not much help, some SWR meters had a top wack of 27MHz while others went to 200MHz, so I think the construction inside may give you a good starting point.
Les
P.S. The power limit of 16 Watts does seem to indicate CB usage.

Alan Stepney · 11th Jul 2009, 5:54 am

It appears to be a fairly standard trough-line construction, hence my comment that it "looks VHF".

However, comparing it to two other meters, one home brew that I made some 30+ years ago and an Avair, it is very innacurate at 2 metres both regarding output power and SWR.

Without major dismantling, it is hard to see all the insides, so there could well be some crucial feature that isnt obvious, so my assumption about VHF, could be wrong.
There is, after all, no reason why that same construction couldnt be used for HF, with some critical part not being visible.

Hence, seeing an advert for it would give the answers.

10th Jul 2009, 3:14 pm	#1
Alan Stepney Rest in Peace Join Date: Feb 2008 Location: Dorset, UK. Posts: 947	Eagle K110 SWR meter Does anyone have any information on this please. Brochure, copy of advert, or similar would be ideal.

10th Jul 2009, 5:31 pm	#2
Top Cap Octode Join Date: Mar 2006 Location: Watford, Hertfordshire, UK. Posts: 1,270	Re: Eagle K110 SWR meter A picture would help as it might give some idea of its complexity. SWR meters are normally pretty basic but some, like the attached photo, can be a bit more complex. Les Attached Thumbnails __________________ Whether the Top Cap is Grid or Anode - touching it will give you a buzz either way!

10th Jul 2009, 7:32 pm	#3
Alan Stepney Rest in Peace Join Date: Feb 2008 Location: Dorset, UK. Posts: 947	Re: Eagle K110 SWR meter I really just need the frequency range, and basics like that. Attached Thumbnails

10th Jul 2009, 9:19 pm	#4
Herald1360 Dekatron Join Date: Feb 2007 Location: Leominster, Herefordshire, UK. Posts: 16,536	Re: Eagle K110 SWR meter What connectors does it have? UHF (SO239)? From the general appearance I should think it's relatively low power and HF only. Can you tickle it with 10 watts or so into a dummy load to see roughly how the adjustment sensitivity feels?

10th Jul 2009, 9:28 pm	#5
Alan Stepney Rest in Peace Join Date: Feb 2008 Location: Dorset, UK. Posts: 947	Re: Eagle K110 SWR meter Yes, it is UHF connectors, but a lot of Japanese equipment used them for 2 metres. The construction looks "VHF", but the power is shown as 16 watts maximum. Was it for HF, or CB, or for 2 metres? I dont have an HF Tx to hand, and it wont read off any of the signal generators I have. Also, it isnt in the 80-81 Eagle catalogue, but someone must know it or have an advert for it somewhere. I hope!

10th Jul 2009, 10:40 pm	#6
Top Cap Octode Join Date: Mar 2006 Location: Watford, Hertfordshire, UK. Posts: 1,270	Re: Eagle K110 SWR meter Hi Alan, you may be able to get some idea by its construction. If it contains lines in a screened enclosure (as attached picture) then you may be able to use it up to 200MHz. But if the construction is for example printed circuit lines then it may have been designed for CB radio. The only real way of testing is by using a non inductive 50 Ohm load on the antenna end and feeding it via a suitable instrument to measure its miss-match at higher frequencies. A network analyser would be nice if you know anyone who has access to one. However I have built some in the past and just used a suitable dummy load on its own, making the assumption that the bridge should give maximum forward but minimum reflected indications on the meter. The acid test then is to reverse everything, placing the load on the transmitter port and injecting a carrier into the antenna port. If the bridge is good, you will see identical results but they will be reversed, i.e. maximum reflected and minimum forward indications. I have checked out some of the meters being offered on the internet but it was not much help, some SWR meters had a top wack of 27MHz while others went to 200MHz, so I think the construction inside may give you a good starting point. Les P.S. The power limit of 16 Watts does seem to indicate CB usage. Attached Thumbnails __________________ Whether the Top Cap is Grid or Anode - touching it will give you a buzz either way!

11th Jul 2009, 5:54 am	#7
Alan Stepney Rest in Peace Join Date: Feb 2008 Location: Dorset, UK. Posts: 947	Re: Eagle K110 SWR meter It appears to be a fairly standard trough-line construction, hence my comment that it "looks VHF". However, comparing it to two other meters, one home brew that I made some 30+ years ago and an Avair, it is very innacurate at 2 metres both regarding output power and SWR. Without major dismantling, it is hard to see all the insides, so there could well be some crucial feature that isnt obvious, so my assumption about VHF, could be wrong. There is, after all, no reason why that same construction couldnt be used for HF, with some critical part not being visible. Hence, seeing an advert for it would give the answers.