Jared:

I was looking at the 53131A specs and the minimum input spec for 100MHz to 2.7GHz is -27dBm and from there to 3Ghz is -21dBm.
I guess actual levels would be less than that , but not significantly or Agilent would have taken credit for it.

For the channel A and B inputs the levels range from 20mV to 40mV (-21dBm to -15dBm if terminated in 50 ohms).

Your board must have a lot of gain at the low end for the minimum input to be below -50dBm for frequencies below 800Mhz as seen in the PNG image you posted.

Like you, I also noticed that the input protection diodes affected the signal levels. More effect than I expected.?

I am currently using two Mini Circuits ERA amplifiers for the gain stage with a 3dB attenuator in line with the input.

My minimum input levels from 750MHz to 3GHz are somewhat in line with the Agilent spec, -34dBm to -21dBm.
At 500Mhz, the input level drops to -13dBm, I think my input cap and those in line may be too small.

ed

On Fri, May 3, 2024 at 10:01 AM, Dave McGuire wrote:

HP-9000 DIO RAM

Dave

Your post helped a lot . I think I found the cloned memory info by Dr. Scott M. Baker :


Maciej

Ed

The connector is part of the machine and the memory card uses PCB edge as connector.
There is a raiser inserted in onto the 3852A processor board like the one below.
The memory card interfaces this raiser.
I was thinking of making a card using? SRAM .? The 4Mbit chips? R1LP0408DSP-5SI (512kx8) would be a good choice.? 2 chips for 1MB card.
Some things I am not sure of are:

• how the? addressing works on these systems
• how the detection of RAM is determined? by the CPU
• how DTACK signal is generated
• what address range should be used (HP had dip switched)
• how address decoding would be done with dip switches for picking range

Maciej

If the CRT has an intact heater & shiny silver getter, it is probably fine. Lack of EHT is more likely to be a problem, especially if there are leaky paper based capacitors in the EHT circuit, or a bad step up transformer.
Also there are several 5AQP type CRTs on ebay, two which look to have been pulled from old oscilloscopes and one very expensive NOS.

David

开云体育

One more generic question: up to now I have never seen any evidence that the CRT is working, if I get to the point of having the whole circutry working again and I discover that the CRT is not recoverable will I be able to find a replacement? I already checked the heater and that one seems to have the right resistance, the look of the gettered surface seems to have the right look too. Thank you for your comments.

The first thing you should try is to reseat the power supply module in the main power supply. This module is similar to a memory module in an old PC, and it plugs into a DIMM socket.

I have a blank display on my HP8563E. The CRT is fine but I found out that -15 VDC power supply is down (LED on A2 is off). I measured nearly 0 V on TP303 (vs TP301) on A6.
Anyone came across the same problem?

Best regards, Michel F6DZK

On 5/3/24 07:20, Ed (scskits) wrote:

If the connector is still available, it would not be difficult to make a 1MB or 8MB static RAM board.
I did one not too long ago for the Data I/O UNISITE that also uses the MC68000.
The original UNISITE board was DRAM with up to eight 9 bit modules.
With the static RAM, the parity was disabled.

Nice!

If that is in fact an HP-9000 DIO RAM board, they've already been cloned. A fellow over in .eu did the design, I had a small run of PCBs done and built a few, and eventually got it working. I had intended to do a production run and sell them, but there wasn't a lot of interest on the vinthpcom list, surprisingly, so there it has sat for the past few years.

-Dave

--
Dave McGuire, AK4HZ
New Kensington, PA

开云体育

Ozan,
Thank you for the tips.? My observations:
1. I was able to verify +15VF, +5A and +10UF voltages directly on A7.? I need to get an extender to really dig into it :-(
2. In the system diagnostics, +10V Reference (presumably +10UF?) is quite unstable
3. In verifying +10UF, I measured at one end of R105, which connects +10UF to V(REF)+ of the DAC in the third converter ref_cal circuit.? Not knowing which end was which, it was easy enough to find the +10UF (and checking with an o-scope it's quite stable, unlike the system diagnostic), but as it happens the other side of R105 has a very small voltage on it (less than 100 mV).? This doesn't seem right to me.??
As I await my extender, any further insights would be appreciated!

If the connector is still available, it would not be difficult to make a 1MB or 8MB static RAM board.
I did one not too long ago for the Data I/O UNISITE that also uses the MC68000.
The original UNISITE board was DRAM with up to eight 9 bit modules.
With the static RAM, the parity was disabled.

ed

Am I too stupid to find it or hasn't it been verified yet?
I'm excited to see the CLIPs.

Tom DG8SAQ

Sorry a correction, by disconnecting the J9P interpanel connector I have disconnected the V33 heater so I could not have had the right voltage out anyway from the -150 supply, regardless I was getting around -165 on C140B. The dV across V34, 80+V, is about right.
Riconnecting J9P only and not J10P the 88V supply should not have worked regularly also since there the 300 V supply contribution is missing? , I am getting 31V instead of 88. Around 200V on the V28 and V29 plates. I tried to regulate the 150V supply and I could do this verya ccurately.

Hi

Try this: ?simon@...

开云体育

I haven't looked up the pinout because I really need to get to sleep, but from the photo this board looks *exactly* like a DIO bus RAM board for an HP-9000 series 300 computer.

-Dave

On May 2, 2024 8:46:01 PM "Maciej Kawalkowski, Liberty Electronics Design and Service LLC" <kawalkowski.m@...> wrote:

Here is a collection of data I have on the Hp 3852a expansion port and memory modules :
Its a Dram module opposed to the SRAM internal memory The memory controller used is National DP8409A memory chips are Siemens 41256 There are 4 banks organized in 9bit most likely for parity checking.
The card pictured must be a 1MB version organized in 4 banks, each bank consisting of 9 chips. The 68000 used in the HP can address 8 bit or 16 bit words . Since the card uses parity bits there needs to be a parity bit controller on it as well.
The 68000 processor used the Asynchronous bus control to read and write memory.

User Davorin on EEVblog traced out most of the pins on the connector. HP 3852A Edge Connector

1 NC

2 NC

3 NC

4 NC

5 NC

6 NC

7 NC

8 NC

9 NC

10 NC

11 NC

12 NC

13 NC

14 NC

15 GND

16 GND

17 NC

18 NC

19 NC

20 NC

21 NC

22 NC

23 GND

24 GND

25 NC

26 NC

27 NC

28 NC

29 NC

30 ???

31 NC

32 NC

33 NC

34 ???

35 GND

36 GND

37 RESET

38 NC

39 GND

40 GND

41 NC

42 NC

43 LDS

44 UDS

45 R/W

46 AS

47 GND

48 GND

49 NC

50 A1

51 A2

52 A3

53 A4

54 A5

55 A6

56 A7

57 A8

58 A9

59 A10

60 A11

61 GND

62 GND

63 A12

64 A13

65 A14

66 A15

67 A16

68 A17

69 A18

70 A19

71 A20

72 A21

73 A22

74 A23

75 GND

76 U27 1820-4147 Pin 4 (74HCT573 Octal Latch?) -> D2

77 D0

78 D1

79 D2

80 D3

81 D4

82 D5

83 D6

84 D7

85 VCC

86 VCC

87 D8

88 D9

89 D10

90 D11

91 D12

92 D13

93 D14

94 D15

95 NC

96 NC

97 NC

98 NC

99 NC

100 NC

From < >

--
Dave McGuire, AK4HZ
New Kensington, PA