FT277ZD Sommerkamp no tx - UK Vintage Radio Repair and Restoration Discussion Forum

Meekoblue · 9th Mar 2018, 3:07 pm

Hello all. I've just acquired, mainly for nostalgic reasons, a FT277ZD which I'm lead to believe is a rebadged Yaesu FT101ZD mark 2 (has WARC bands and AM but without notch filter).

I'm a very rusty ex SHARP electronics tech mot familiar with consumer audio equipment so I can solder and not afraid of HT, but I could use some pointers for this set.

Just picked it up yesterday and receives ok but driven gently into a G5RV I'm not registering any power output.

Where should I start looking? Any common faults?
Many thanks in advance!
Meeko
M0FVD

G6Tanuki · 9th Mar 2018, 3:27 pm

Not familiar with that particular radio but on quite a few similar-era Yaesus there is a multi-way plug on the rear of the chassis which can be linked in a way which disables the PA but still allows a low-power output to drive a VHF/UHF transverter.

ex seismic · 9th Mar 2018, 3:27 pm

Do you have the manual, i.e. are you familiar with the tune up procedure?

On the back there is a multi-way socket, (11 way?). There is a link in there for the transmit valve heaters I think it was. No plug, no Tx.

Gordon
G7KNS

Meekoblue · 9th Mar 2018, 5:13 pm

Hi guys thanks for the replies. Had a quick poke around and found the accessory plug on the back *doesnt* have heater supply. The plug has the link pin 1-2 but 0volt on it whit heaters turned on. May be a relatively easy problem if I can squint at the circuit and trace it. I believe it's a 12.6v dc supply that also feeds the receiver so it's looking promising.

ex seismic · 9th Mar 2018, 8:03 pm

For the 101ZD pins 1 and 2 supply the heaters of the driver and PA valves with either 12vac or 12vdc from board REC A via the front panel Tx power switch. There is a relay on REC A which switches from normal ac supply to dc supply, I guess when the optional dc power pack is used.

Gordon

Radio Wrangler · 10th Mar 2018, 7:41 am

The Yaesu radios sold in the UK in that era were brought in by SMC, their 'authorised' agent and carried Yaesu branding. Some people brought their own radios in from the US to save a bit of money, but those were branded Yaesu too. At that time, the Sommerkamp name was used in parts of mainland Europe where prices were marked-up even more than the UK. So Sommerkamp gear was quite rare here in amateur radio circles, usually brought in by someone who had been living in Germany and had bought it there.

There were a couple of shops doing 'grey' imports, but they brought their sets in from countries where they were priced cheaper than the UK, not dearer. Yaesu branding was usual.

However, for some unknown reason, Sommerkamp badged equipment was very highly sought after by the illegal CB brigade, much more so than the same set with a Yaesu badge on it. Their attempts to convert them to 'their' frequency bands were not very good in most cases, and often unreliable. Sets which became beyond the ability of their group's repairers tended to get sold at basket-case prices.

I came across a few which had been bought by radio amateurs because they were cheap. Undoing the modifications and workmanship issues was not fun. I once held up a crystal-mixer LO board before a few amateurs who'd brought the set round, and announced, Cluedo-fashion "It was the Marx brothers, in the kitchen, with the blowlamp!"

So, if I see anything here with a Sommerkamp badge, my first step is to look for illicit modifications.

Harry Leeming G3LLL used to write a magazine column on repairing amateur radio gear. He specialised in Yaesu and passed on a lot of wisdom and tips. It's worth tracking them down on that American website with the big collection of scanned magazines.

If your radio receives correctly on all bands, it looks like you've got one which hasn't been got-at.

Receiving proves that the LO frequency converter is OK and the IF is OK so that most probably leaves the three valves - and the T/R switching. The routine is to check for heaters and check for HT. There is enough current available on the HT supplies to be deadly. Then it's a matter of following the signal through the stages to see where it stops.

David GM4ZNX

Meekoblue · 10th Mar 2018, 12:25 pm

Thanks David for the background! So far it seems entirely genuine and unmodified. Problem seems to be complete absence of heater supply. Need to check the relay, doesn't appear to be operating....

Meekoblue · 10th Mar 2018, 11:19 pm

Fixed it!
Faulty Heater switch. Jumpers the 12VAC across the switch and it powers up and tunes up. Few noisy pots but no evidence of 11m mods. In fact it's marked inside with a GW0xxx callsign. Presumably original owner.

Also: thought the radio was a bit "deaf" but on inspection found I had a break in feeder line. First calls netted nothng but replied to an EA7's CQ call and got a 5&5 back. Nice to know I've not bought a lemon!

Thanks for the replies guys!

9th Mar 2018, 3:07 pm	#1
Meekoblue Retired Dormant Member Join Date: Mar 2018 Location: Manchester, UK. Posts: 14	FT277ZD Sommerkamp no tx Hello all. I've just acquired, mainly for nostalgic reasons, a FT277ZD which I'm lead to believe is a rebadged Yaesu FT101ZD mark 2 (has WARC bands and AM but without notch filter). I'm a very rusty ex SHARP electronics tech mot familiar with consumer audio equipment so I can solder and not afraid of HT, but I could use some pointers for this set. Just picked it up yesterday and receives ok but driven gently into a G5RV I'm not registering any power output. Where should I start looking? Any common faults? Many thanks in advance! Meeko M0FVD

9th Mar 2018, 3:27 pm	#2
G6Tanuki Dekatron Join Date: Apr 2012 Location: Wiltshire, UK. Posts: 13,996	Re: FT277ZD Sommerkamp no tx Not familiar with that particular radio but on quite a few similar-era Yaesus there is a multi-way plug on the rear of the chassis which can be linked in a way which disables the PA but still allows a low-power output to drive a VHF/UHF transverter.

9th Mar 2018, 3:27 pm	#3
ex seismic Heptode Join Date: Sep 2009 Location: Tonbridge, Kent, UK. Posts: 686	Re: FT277ZD Sommerkamp no tx Do you have the manual, i.e. are you familiar with the tune up procedure? On the back there is a multi-way socket, (11 way?). There is a link in there for the transmit valve heaters I think it was. No plug, no Tx. Gordon G7KNS

9th Mar 2018, 5:13 pm	#4
Meekoblue Retired Dormant Member Join Date: Mar 2018 Location: Manchester, UK. Posts: 14	Re: FT277ZD Sommerkamp no tx Hi guys thanks for the replies. Had a quick poke around and found the accessory plug on the back doesnt have heater supply. The plug has the link pin 1-2 but 0volt on it whit heaters turned on. May be a relatively easy problem if I can squint at the circuit and trace it. I believe it's a 12.6v dc supply that also feeds the receiver so it's looking promising.

9th Mar 2018, 8:03 pm	#5
ex seismic Heptode Join Date: Sep 2009 Location: Tonbridge, Kent, UK. Posts: 686	Re: FT277ZD Sommerkamp no tx For the 101ZD pins 1 and 2 supply the heaters of the driver and PA valves with either 12vac or 12vdc from board REC A via the front panel Tx power switch. There is a relay on REC A which switches from normal ac supply to dc supply, I guess when the optional dc power pack is used. Gordon

10th Mar 2018, 7:41 am	#6
Radio Wrangler Moderator Join Date: Mar 2012 Location: Fife, Scotland, UK. Posts: 22,868	Re: FT277ZD Sommerkamp no tx The Yaesu radios sold in the UK in that era were brought in by SMC, their 'authorised' agent and carried Yaesu branding. Some people brought their own radios in from the US to save a bit of money, but those were branded Yaesu too. At that time, the Sommerkamp name was used in parts of mainland Europe where prices were marked-up even more than the UK. So Sommerkamp gear was quite rare here in amateur radio circles, usually brought in by someone who had been living in Germany and had bought it there. There were a couple of shops doing 'grey' imports, but they brought their sets in from countries where they were priced cheaper than the UK, not dearer. Yaesu branding was usual. However, for some unknown reason, Sommerkamp badged equipment was very highly sought after by the illegal CB brigade, much more so than the same set with a Yaesu badge on it. Their attempts to convert them to 'their' frequency bands were not very good in most cases, and often unreliable. Sets which became beyond the ability of their group's repairers tended to get sold at basket-case prices. I came across a few which had been bought by radio amateurs because they were cheap. Undoing the modifications and workmanship issues was not fun. I once held up a crystal-mixer LO board before a few amateurs who'd brought the set round, and announced, Cluedo-fashion "It was the Marx brothers, in the kitchen, with the blowlamp!" So, if I see anything here with a Sommerkamp badge, my first step is to look for illicit modifications. Harry Leeming G3LLL used to write a magazine column on repairing amateur radio gear. He specialised in Yaesu and passed on a lot of wisdom and tips. It's worth tracking them down on that American website with the big collection of scanned magazines. If your radio receives correctly on all bands, it looks like you've got one which hasn't been got-at. Receiving proves that the LO frequency converter is OK and the IF is OK so that most probably leaves the three valves - and the T/R switching. The routine is to check for heaters and check for HT. There is enough current available on the HT supplies to be deadly. Then it's a matter of following the signal through the stages to see where it stops. David GM4ZNX __________________ Can't afford the volcanic island yet, but the plans for my monorail and the goons' uniforms are done

10th Mar 2018, 12:25 pm	#7
Meekoblue Retired Dormant Member Join Date: Mar 2018 Location: Manchester, UK. Posts: 14	Re: FT277ZD Sommerkamp no tx Thanks David for the background! So far it seems entirely genuine and unmodified. Problem seems to be complete absence of heater supply. Need to check the relay, doesn't appear to be operating....

10th Mar 2018, 11:19 pm	#8
Meekoblue Retired Dormant Member Join Date: Mar 2018 Location: Manchester, UK. Posts: 14	Fixed it! Faulty Heater switch. Jumpers the 12VAC across the switch and it powers up and tunes up. Few noisy pots but no evidence of 11m mods. In fact it's marked inside with a GW0xxx callsign. Presumably original owner. Also: thought the radio was a bit "deaf" but on inspection found I had a break in feeder line. First calls netted nothng but replied to an EA7's CQ call and got a 5&5 back. Nice to know I've not bought a lemon! Thanks for the replies guys!