anyone hear handy with hf amps?.

bassy

hi i have a yaesu FL 2100B amplifier,but i don,t think its fully working at all.
2 tubes were lighting up,only 1 tube lighting up now.maybe the tubes were bad when i bought it.

was trying to tune it up today,it blew a fuse in the plug,so i replaced the fuse plugged it back in and it powered up ok.

so tonite i hooked it up to my icom radio and tryed tuning it with plate and load,no luck as far as i can see.but i,m new to hf amps.

anyone hear be able to take a look at it or indeed be able to repair it?,any help would be truly appreciated guys.

watty

You need to initially tune it with a suitable dummy load (1kW peak, 100W continious would do for quick tuning).

It may not tune properly with one tube gone.

You also need a 1KW rated Transmatch/ATU even for a single band aerial.
You need extremely good earthing.
You need very good layout and cables or you can get RF feedback very easily.

I do know a couple of people that can fix them, but it would be expensive (and Limerick). All of the people I know that use FL2100 or similar live in countryside with no close neighbours. There is not "modern" level of filtering and it may produce considerable power in FM Radio and TV bands. Also affect Cable TV, MMDS downleads and Buglar alarms. ESPECIALLY if the earthing or aerial is unsuitable or unmatched.

watty

Do note that nothing illegal can be discussed on Boards.

The legal usages for an FL2100 are limited to licenced use of particular bands with due care. We can't discuss other use. (Boards and the OP could get in trouble). This is Boards.ie policies, see stickies.

So if we follow those rules the thread can remain open/undeleted

bassy

will keep this well on the legal side watty,2 new tubes for it cost $98.00 dollars 0r less from the states and with todays euro/dollar exchange rate.

its very clean looking amp,just that i don,t really know any one around my area that could look at it.

watty

There are places also in UK good for valves.

bassy

watty would you know anyone up around the southeast that could take a look at it?,thanks.

snowman707

be careful messing around in these amps ,

even when plugged out for hours you can get more than you bargain for ,

bassy

thanks snowman, i,m well aware of the high voltage currents in this amp even when plugged out for hours.

just been put in touch with a guy who has huge experience with hf valve equiptment,said should be no trouble in checking out my amp.

so thanks to all the guys who replied.

watty

I tried to measure the 450V DC on the 6146 valve anode in FT101ZD radio using 5Eur multimeter on 1000V range. It lit up in a blue flash. The cheap meters are probably only good to 300VDC and 250V AC. I have an AVO now and it very happily measures up to 1000V on regular socket and 3KV on aux socket.

An AVO is quite cheap on eBay and needed if you want to check stuff on a valve PA of any kind. The RF also makes most digital meters go mad.

You need to adjust bias currents and check the -160V or +2000VDC etc is in spec on a linear.

Also the AVO will slowly discharge the high voltage as it is 5kOhm to 20kOhm per volts or similar depending on range (AV or DC) and digital meters are 1M to 10M input.

Fuzzy Clam

bassy wrote: »

2 tubes were lighting up,only 1 tube lighting up now.maybe the tubes were bad when i bought it.

.

The lighting up is the 6.3v heaters, not the HT,so it looks like the heater has gone in one bottle. I don't have the pin outs to hand but its easy to check with a continuity meter for a short or open circuit with the valves out of the socket.

If the guy who you've been put in contact with doesn't come through, I may be able to help. I'm sure I have a couple of 6146s kicking about here.

bassy

no problem fuzzy and thanks for your kind input,will let you know how i get on cheers.

Fuzzy Clam wrote: »

The lighting up is the 6.3v heaters, not the HT,so it looks like the heater has gone in one bottle. I don't have the pin outs to hand but its easy to check with a continuity meter for a short or open circuit with the valves out of the socket.

If the guy who you've been put in contact with doesn't come through, I may be able to help. I'm sure I have a couple of 6146s kicking about here.

Tactical

bassy wrote: »

hi i have a yaesu FL 2100B amplifier

Naturally you'll make sure that your erp is no higher than the legal limit here in Ireland when using this amplifier?

bassy

hi tactical yes indeed,i have no intentions of breaking any laws.

Tactical wrote: »

Naturally you'll make sure that your erp is no higher than the legal limit here in Ireland when using this amplifier?

Tactical

Good stuff, glad to hear that.

Out of curiosity what were you trying to load this amp into? The acceptable antenna impedance range is quite narrow and like Watty has said a tuner capable of handling the power this amp can develop is essential. A dummy load is also essential and the correct way to set up.

Be very careful when tuning this amp and working around it. Its possible to get a serious RF burn with these power levels.

Also if you have the top cover off, never try to operate the amp as there is a safety feature which shorts out the HT supply and damage may be caused.

bassy

connected it to a icom-735 via special din plug connection cable.

Tactical

That would be essential as there is no RF sensing on the amplifier.

watty

Fuzzy Clam wrote: »

The lighting up is the 6.3v heaters, not the HT,so it looks like the heater has gone in one bottle. I don't have the pin outs to hand but its easy to check with a continuity meter for a short or open circuit with the valves out of the socket.

If the guy who you've been put in contact with doesn't come through, I may be able to help. I'm sure I have a couple of 6146s kicking about here.

The FT101ZD uses 6146s, but the FL2100 uses something more powerful. It's a bigger pair valves.

Fuzzy Clam

watty wrote: »

The FT101ZD uses 6146s, but the FL2100 uses something more powerful. It's a bigger pair valves.

I stand corrected. i was going by previous posts. 572b's

If I had no experience with tube equip, I probably woundn't start with a large amp like this.

Tactical

Very sensible advice Fuzzy.

I assume that you are able to calculate the RF O/P from the unit Bassy?

bassy

Tactical wrote: »

Very sensible advice Fuzzy.

I assume that you are able to calculate the RF O/P from the unit Bassy?

i have a highly technical instrument to do that,its called a power meter bird 43

Tactical

Very nice

pixbyjohn

Fuzzy Clam wrote: »

The lighting up is the 6.3v heaters, not the HT,so it looks like the heater has gone in one bottle. I don't have the pin outs to hand but its easy to check with a continuity meter for a short or open circuit with the valves out of the socket.

If the guy who you've been put in contact with doesn't come through, I may be able to help. I'm sure I have a couple of 6146s kicking about here.

6146s wont suit a 2100 linear.

Fuzzy Clam

pixbyjohn wrote: »

6146s wont suit a 2100 linear.

Read posts # 17 & 18