Re: [Drakelist] Receiver protection lamp
List - My memory misfired. The TR-7 Receiver Protector was the RP-700 not the RP-7. http://www.dproducts.be/drake_Museum/nouvelle6.htm Over the years of Drake ham production. Some kind of Receiver Protection was model dependent. 73 Bob W7AVK On 10/16/2011 9:25 AM, Kihwal Lee wrote: Just to clarify, early TR-3's don't have the lamp. Kihwal, K9SUL . ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Receiver protection lamp
Just to clarify, early TR-3's don't have the lamp. Kihwal, K9SUL - Original Message From: Garey Barrell To: Bob W7AVK Cc: drakelist@zerobeat.net Sent: Sun, October 16, 2011 11:08:01 AM Subject: Re: [Drakelist] Receiver protection lamp Bob - I've never seen one of those. I thought they had the gas discharge/ gas plasma transient suppressor (90L) used in the later TR-7s.?? It was to protect the SS front end of the TR-7 / R-7 against static discharge and/or nearby lightning strikes. The tube fires at 90V. 73, Garey - K4OAH St Charles, IL Drake 2-B, 2-C/2-NT, 4-A, 4-B, C-Line and TR-4/C Service Supplement CDs Bob W7AVK wrote: > List - The same lamp was used by Drake in an option for the TR-7 and > R7s. Called RP-7. Was sold as a "receiver protector" in a small box that > was inserted in the coax before the receiver input. > > If someone needs one of the lamps I have a couple. > > Also have a small number of the hard to find PIN diodes used in the TR-7 > series. > > 73 Bob W7AVK > ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Receiver protection lamp
Bob - I've never seen one of those. I thought they had the gas discharge/ gas plasma transient suppressor (90L) used in the later TR-7s.?? It was to protect the SS front end of the TR-7 / R-7 against static discharge and/or nearby lightning strikes. The tube fires at 90V. 73, Garey - K4OAH St Charles, IL Drake 2-B, 2-C/2-NT, 4-A, 4-B, C-Line and TR-4/C Service Supplement CDs Bob W7AVK wrote: List - The same lamp was used by Drake in an option for the TR-7 and R7s. Called RP-7. Was sold as a "receiver protector" in a small box that was inserted in the coax before the receiver input. If someone needs one of the lamps I have a couple. Also have a small number of the hard to find PIN diodes used in the TR-7 series. 73 Bob W7AVK ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Receiver protection lamp
List - The same lamp was used by Drake in an option for the TR-7 and R7s. Called RP-7. Was sold as a "receiver protector" in a small box that was inserted in the coax before the receiver input. If someone needs one of the lamps I have a couple. Also have a small number of the hard to find PIN diodes used in the TR-7 series. 73 Bob W7AVK On 10/16/2011 8:28 AM, Garey Barrell wrote: As others have said, it's a protective 'fuse' for the receiver in the TR-3/4 series transceivers. It's a worthwhile addition because again, the TR-3/4 series is an EXCELLENT 'SSB Transceiver for _Mobile_ operation'. It's marginal for other uses, but for it's design goal, terrific! Mobile use is WHY the bulb is necessary. You won't have an 18-wheeler carrying a 2 kW CB transmitter pull up next to your home shack, but Even a 200 W transmitter with it's vertical antenna only a few feet away from yours can fry an input transformer.. I have seen the bulb in a TR-4 show a good glow with another nearby 200 W transmitter on a different antenna and band. The #12 bulb is identical to the #47 bulb electrically, just with shorter leads. They are readily available from the on-line bulb dealers, and shouldn't be replaced with a piece of wire, especially if operated mobile. Obviously an open bulb or even corrosion on the leads can severely impact receiver sensitivity, second only to that %%#%$ 'TCVR/RCVR' slide switch on the left side! 73, Garey - K4OAH St Charles, IL . ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Receiver protection lamp
As others have said, it's a protective 'fuse' for the receiver in the TR-3/4 series transceivers. It's a worthwhile addition because again, the TR-3/4 series is an EXCELLENT 'SSB Transceiver for _Mobile_ operation'. It's marginal for other uses, but for it's design goal, terrific! Mobile use is WHY the bulb is necessary. You won't have an 18-wheeler carrying a 2 kW CB transmitter pull up next to your home shack, but Even a 200 W transmitter with it's vertical antenna only a few feet away from yours can fry an input transformer.. I have seen the bulb in a TR-4 show a good glow with another nearby 200 W transmitter on a different antenna and band. The #12 bulb is identical to the #47 bulb electrically, just with shorter leads. They are readily available from the on-line bulb dealers, and shouldn't be replaced with a piece of wire, especially if operated mobile. Obviously an open bulb or even corrosion on the leads can severely impact receiver sensitivity, second only to that %%#%$ 'TCVR/RCVR' slide switch on the left side! 73, Garey - K4OAH St Charles, IL Drake 2-B, 2-C/2-NT, 4-A, 4-B, C-Line and TR-4/C Service Supplement CDs Neil M Califano wrote: What is this???: ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Receiver protection lamp
- Original Message - From: "Robert Ladden" To: Sent: Saturday, October 15, 2011 6:07 PM Subject: Re: [Drakelist] Receiver protection lamp The TR-3/4 had a fuse lamp between the receiver and antenna to protect the receiver. Since these were mobile rigs the large whip antennas could hit light fixtures in garages (my theory). 73, Bob WW3QB More likely to protect the input circuit if someone else fires up a tranmitter nearby, it would also protect the input from static accumulation from friction on the antenna and from driving through a lightening storm. Serves a similar purpose when used in a fixed location. The lamp is a twin-post lamp with similar characteristics to a No.47 but the base arrangement has less reactance at radio frequencies. I managed to pop one while trouble shooting a TR-4 and had trouble getting replacements locally. Keeping a spare available is a good idea even though they are likely to last forever. If the TR-4 receiver seems dead and its nothing else the lamp is worth looking at. If its open or the contacts are dirty the effect is of no antenna being connected. -- Richard Knoppow Los Angeles WB6KBL dickb...@ix.netcom.com ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
Re: [Drakelist] Receiver protection lamp
The TR-3/4 had a fuse lamp between the receiver and antenna to protect the receiver. Since these were mobile rigs the large whip antennas could hit light fixtures in garages (my theory). 73, Bob WW3QB From: Neil M Califano To: Drakelist@zerobeat.net Sent: Saturday, October 15, 2011 8:54 PM Subject: [Drakelist] Receiver protection lamp What is this???: http://www.ebay.com/itm/RL-Drake-Receiver-Protection-Lamp-4-Line-Receivers-/360399257957?pt=LH_DefaultDomain_0&hash=item53e9784165 ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
[Drakelist] Receiver protection lamp
What is this???: http://www.ebay.com/itm/RL-Drake-Receiver-Protection-Lamp-4-Line-Receivers-/360399257957?pt=LH_DefaultDomain_0&hash=item53e9784165 ___ Drakelist mailing list Drakelist@zerobeat.net http://mailman.zerobeat.net/mailman/listinfo/drakelist
